General Description
The MAX9860 is a low-power, voiceband, mono audio
codec designed to provide a complete audio solution
for wireless voice headsets and other mono voice audio
devices. Using an on-chip bridge-tied load mono head-
phone amplifier, the MAX9860 can output 30mW into a
32Ωearpiece while operating from a single 1.8V power
supply. Very low power consumption makes it an ideal
choice for battery-powered applications.
The MAX9860’s flexible clocking circuitry utilizes com-
mon system clock frequencies ranging from 10MHz to
60MHz, eliminating the need for an external PLL and
multiple crystal oscillators. Both the ADC and DAC sup-
port sample rates of 8kHz to 48kHz in either synchro-
nous or asynchronous operation. Both master and slave
timing modes are supported.
Two differential microphone inputs are available with a
user-programmable preamplifier and programmable
gain amplifier. Automatic gain control with selectable
attack/release times and signal threshold allows maxi-
mum dynamic range. A noise gate with selectable
threshold provides a means to quiet the channel when
no signal is present. Both the DAC and ADC digital filters
provide full attenuation for out-of-band signals as well as
a 5th order GSM-compliant digital highpass filter. A digi-
tal side tone mixer provides loopback of the micro-
phones/ADC signal to the DAC/headphone output.
Serial DAC and ADC data is transferred over a flexible
digital I2S-compatible interface that also supports TDM
mode. Mode settings, volume control, and shutdown are
programmed through a 2-wire, I2C-compatible interface.
The MAX9860 is fully specified over the -40°C to +85°C
extended temperature range and is available in a low-
profile, 4mm x 4mm, 24-pin thin QFN package.
Applications
Audio Headsets
Portable Navigation Device
Mobile Phones
Smart Phones
VoIP Phones
Audio Accessories
Features
♦1.8V Single-Supply Operation
♦Digital Highpass Elliptical Filters with Notch for
217Hz (GSM)
♦Mono 30mW BTL Headphone Amplifier
♦Dual Low-Noise Microphone Inputs
♦Automatic Microphone Gain Control and Noise
Gate
♦90dB DAC DR (fS= 48kHz)
♦81dB ADC DR (fS= 48kHz)
♦Supports Master Clock Frequencies from 10MHz
to 60MHz
♦Supports Sample Rates from 8kHz to 48kHz
♦Flexible Digital Audio Interface
♦Clickless/Popless Operation
♦2-Wire, I2C-Compatible Control Interface
♦Available in 24-Pin, Thin QFN, 4mm x 4mm x
0.8mm Package
MAX9860
16-Bit Mono Audio Voice Codec
________________________________________________________________
Maxim Integrated Products
1
19-4349; Rev 1; 9/09
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Ordering Information
PART TEMP RANGE PIN-PACKAGE
MAX9860ETG+ -40°C to +85°C 24 TQFN-EP*
+
Denotes a lead-free/RoHS-compliant package.
*
EP = Exposed pad.
ADC
ADC
DIGITAL
AUDIO
INTERFACE
DIGITAL
FILTERING
AND
MIXERS
DIFF
MIC
DIFF
MIC
DAC
AVDD AND DVDD
1.7V TO 1.9V
DVDDIO
1.7V TO 3.6V
CLOCK
CONTROL
DIGITAL AUDIO
INPUT/OUTPUT
I2C
INTERFACE
MAX9860
Simplified Block Diagram
Pin Configuration and Typical Operating Circuit appear at
end of data sheet.
MAX9860
16-Bit Mono Audio Voice Codec
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VAVDD = VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF, CMICBIAS =
CPREG = CREG = 1µF, AVPRE = +20dB, AVMICPGA = 0dB, MCLK = 13MHz, LRCLK = 8kHz, TA= TMIN to TMAX, unless otherwise noted.
Typical values are at TA= +25°C.) (Note 2)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
(Voltages referenced to AGND.)
DVDDIO, SDA, SCL, IRQ.......................................-0.3V to +3.6V
AVDD, DVDD............................................................-0.3V to +2V
AGND, DGND, MICGND .......................................-0.3V to +0.3V
OUTP, OUTN, PREG, REF, MICBIAS ......-0.3V to (AVDD + 0.3V)
MICLP, MICLN, MICRP, MICRN, REG ....-0.3V to (PREG + 0.3V)
MCLK, LRCLK, BCLK,
SDOUT, SDIN..................................-0.3V to (DVDDIO + 0.3V)
Continuous Power Dissipation (TA= +70°C)
24-Pin TQFN (derate 27.8mW/°C above +70°C,
multilayer board) ......................................................2222mW
Junction-to-Ambient Thermal Resistance (θJA) (Note 1)
24-Pin TQFN (derate 27.8mW/°C above +70°C,
multilayer board) ........................................................36°C/W
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
AVDD (inferred from HP output PSRR) 1.7 1.8 1.9
DVDD (inferred from codec performance
tests) 1.7 1.8 1.9
Supply Voltage Range
DVDDIO 1.7 1.8 3.6
V
AVDD 1.46 2.2
DAC playback mode
(48kHz) DVDD 1.05 1.6
AVDD 4.08 5.7
Full operation
8kHz mono ADC + DAC DVDD 0.78 1.0
AVDD 6.17 9.0
Full operation
8kHz stereo ADC + DAC DVDD 0.8 1.2
AVDD 5.38 8.0
Total Supply Current
(Note 3) IAVDD+DVDD
Stereo ADC only (48kHz) DVDD 1.68 2.2
mA
AVDD 0.56 5
Shutdown Supply Current ISHDN TA = +25°C DVDD +
DVDDIO 1.65 5 µA
Shutdown to Full Operation 10 ms
DAC (Note 4)
Gain Error ±1 ±5 %
Dynamic Range (Note 5) DR
+0dB volume setting, fS = 8kHz,
measured at headphone output,
TA = +25°C
84 90 dB
DAC Full-Scale Output 1V
RMS
fS = 8kHz 1.2
DAC Path Phase Delay
f = 1kHz, 0dBFS, HP
filter disabled, digital
input to analog output fS = 16kHz 0.59
ms
Total Harmonic Distortion + Noise THD+N f = 1kHz, MCLK = 12.288MHz,
LRCLK = 48kHz -87 dB
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
MAX9860
16-Bit Mono Audio Voice Codec
_______________________________________________________________________________________ 3
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
f = 1kHz, VRIPPLE = 100mVP-P,
AVPGA = 0dB 94
Power-Supply Rejection Ratio PSRR
f = 10kHz, VRIPPLE = 100mVP-P,
AVPGA = 0dB 71
dB
DAC LOWPASS DIGITAL FILTER
With respect to fS within ripple; fS = 8kHz
to 48kHz
0.448 x
fSHz
Passband Cutoff fPLP
-3dB cutoff 0.451 fS
Passband Ripple f < fPLP ±0.1 dB
Stopband Cutoff fSLP With respect to fS; fS = 8kHz to 48kHz 0.476 x
fSHz
Stopband Attenuation f > fSLP, f = 20Hz to 20kHz 75 dB
DAC HIGHPASS DIGITAL FILTER
DVFLT = 0x1
(elliptical for 16kHz GSM)
0.0161
x fS
DVFLT = 0x2
(500Hz Butterworth for 16kHz)
0.0312
x fS
DVFLT = 0x3
(elliptical for 8kHz GSM)
0.0321
x fS
DVFLT = 0x4
(500Hz Butterworth for 8kHz)
0.0625
x fS
5th Order Passband Cutoff
(-3dB from Peak, I2C Register
Programmable) (Note 6)
fDHPPB
DVFLT = 0x5
(200Hz Butterworth for 48kHz)
0.0042
x fS
Hz
DVFLT = 0x1
(elliptical for 16kHz GSM)
0.0139
x fS
DVFLT = 0x2
(500Hz Butterworth for 16kHz)
0.0156
x fS
DVFLT = 0x3
(elliptical for 8kHz GSM)
0.0279
x fS
DVFLT = 0x4
(500Hz Butterworth for 8kHz)
0.0312
x fS
5th Order Stopband Cutoff
(-30dB from Peak, I2C Register
Programmable) (Note 6)
fDHPSB
DVFLT = 0x5
(200Hz Butterworth for 48kHz)
0.0021
x fS
Hz
DC Blocking DCAtten DVFLT ≠ 0x0 90 dB
ADC
Full-Scale Input Voltage 0dBFS Differential MIC Input, AVPRE = 0dB,
AVPGA = 0dB 1V
P-P
Channel Gain Mismatch ±0.3 %
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF, CMICBIAS =
CPREG = CREG = 1µF, AVPRE = +20dB, AVMICPGA = 0dB, MCLK = 13MHz, LRCLK = 8kHz, TA= TMIN to TMAX, unless otherwise noted.
Typical values are at TA= +25°C.) (Note 2)
MAX9860
16-Bit Mono Audio Voice Codec
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF, CMICBIAS =
CPREG = CREG = 1µF, AVPRE = +20dB, AVMICPGA = 0dB, MCLK = 13MHz, LRCLK = 8kHz, TA= TMIN to TMAX, unless otherwise noted.
Typical values are at TA= +25°C.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
fS = 8kHz, AVPRE = 0dB,
A-weighted from 20Hz to fS/2 81
Dynamic Range (Note 5) DR
fS = 48kHz, AVPRE = 0dB, TA = +25°C 75 83
dB
fS = 8kHz 1.2
ADC Phase Delay
f = 1kHz, 0dBFS, HP filter
disabled, analog input to
digital output fS = 16kHz 0.61
ms
Total Harmonic Distortion THD f = 1kHz, fS = 48kHz, TA = +25°C -70 -75 dB
f = 1kHz, VRIPPLE = 100mVP-P,
AVPGA = 0dB 82
Power-Supply Rejection Ratio PSRR
f = 10kHz, VRIPPLE = 100mVP-P,
AVPGA = 0dB 76
dB
Channel Crosstalk Driven channel at -1dBFS, f = 1kHz -92 dB
ADC LOWPASS DIGITAL FILTER
With respect to fS within ripple;
fS = 8kHz to 48kHz
0.445 x
fSHz
Passband Cutoff fPLP
-3dB cutoff 0.449 fS
Passband Ripple f < fPLP ±0.1 dB
Stopband Cutoff fSLP With respect to fS; fS = 8kHz to 48kHz 0.469 x
fSHz
Stopband Attenuation f > fSLP 74 dB
ADC HIGHPASS DIGITAL FILTER
AVFLT = 0x1 (elliptical for 16kHz GSM) 0.0161
x fS
AVFLT = 0x2 (500Hz Butterworth for
16kHz)
0.0312
x fS
AVFLT = 0x3 (elliptical for 8kHz GSM) 0.0321
x fS
AVFLT = 0x4
(500Hz Butterworth for 8kHz)
0.0625
x fS
5th Order Passband Cutoff
(-3dB from Peak, I2C Register
Programmable) (Note 6)
fAHPPB
AVFLT = 0x5
(200Hz Butterworth for 48kHz)
0.0042
x fS
Hz
MAX9860
16-Bit Mono Audio Voice Codec
_______________________________________________________________________________________ 5
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF, CMICBIAS =
CPREG = CREG = 1µF, AVPRE = +20dB, AVMICPGA = 0dB, MCLK = 13MHz, LRCLK = 8kHz, TA= TMIN to TMAX, unless otherwise noted.
Typical values are at TA= +25°C.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
AVFLT = 0x1
(elliptical for 16kHz GSM)
0.0139
x fS
AVFLT = 0x2
(500Hz Butterworth for 16kHz)
0.0156
x fS
AVFLT = 0x3
(elliptical for 8kHz GSM)
0.0279
x fS
AVFLT = 0x4
(500Hz Butterworth for 8kHz)
0.0312
x fS
5th Order Stopband Cutoff
(-30dB from peak, I2C Register
Programmable) (Note 6)
fAHPSB
AVFLT = 0x5
(200Hz Butterworth for 48kHz)
0.0021
x fS
Hz
DC Blocking DCATTEN AVFLT ≠ 0x0 90 dB
CLOCKING
MCLK Input Frequency MCLK is not required to be synchronous
or related to the desired LRCLK data rate 10 60 MHz
MCLK Duty Cycle 40 50 60 %
Maximum MCLK Input Jitter For guaranteed performance limits 100 psRMS
LRCLK Data Rate Frequency 8 48 kHz
LRCLK PLL Lock Time 12 25 ms
LRCLK Acceptable Jitter for
Maintaining PLL Lock ±20 ns
MONO HEADPHONE AMPLIFIER
RL = 16Ω30 50
Output Power POUT f = 1kHz, THD+N ≤ 1%
TA = +25°C RL = 32Ω33 mW
RL = 32Ω, POUT = 25mW, f = 1kHz 0.05
Total Harmonic Distortion + Noise THD+N RL = 16Ω, POUT = 25mW, f = 1kHz 0.08 %
Dynamic Range (Note 5) DR +0dB volume setting, DAC input at
fS = 8kHz to 48kHz 90 dB
AVDD = 1.7V to 1.9V 60 84
VRIPPLE = 100mVP-P, f = 217Hz 86Power-Supply Rejection Ratio PSRR
VRIPPLE = 100mVP-P, f = 20kHz 71
dB
Output Offset Voltage VOS VOUTP - VOUTN, TA =+25°C ± 0.25 ± 1 mV
RL = 32Ω500
Capacitive Drive Capability No sustained oscillations RL = ∞100 pF
Click-and-Pop Level Peak voltage into/out of shutdown, 32sps,
A-weighted -70 dBV
MAX9860
16-Bit Mono Audio Voice Codec
6 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF, CMICBIAS =
CPREG = CREG = 1µF, AVPRE = +20dB, AVMICPGA = 0dB, MCLK = 13MHz, LRCLK = 8kHz, TA= TMIN to TMAX, unless otherwise noted.
Typical values are at TA= +25°C.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
MICROPHONE AMPLIFIER
PAM = 00 Off
PAM = 01 -0.5 0 +0.5
PAM = 10 19 20 21
Preamplifier Gain AVPRE TA = +25°C
PAM = 11 29 30 31
dB
PGAM = 0x14–0x1F 0
MIC PGA Gain AVMICPGA PGAM = 0x00 +20 dB
MIC PGA Gain Step Size 1dB
Common-Mode Rejection Ratio CMRR VIN = 100mVP-P at 217Hz 50 dB
MIC Input Resistance RIN_MIC All gain settings, measured at
MICLN/MICRN 30 50 kΩ
MIC Input Bias Voltage 0.7 0.8 0.9 V
AVPRE = 0dB, AVMICPGA = 0dB,
VIN = 1VP-P, f = 1kHz -75 dB
Total Harmonic Distortion + Noise THD+N AVPRE = +30dB, AVMICPGA = 0dB,
VIN = 31mVP-P, f = 1kHz -66 dB
AVDD = 1.7V to 1.9V 60 95 dB
VRIPPLE = 100mV at 1kHz, input referred 82 dB
MIC Power-Supply Rejection
Ratio PSRR
VRIPPLE = 100mV at 10kHz, input referred 76 dB
MICROPHONE BIAS
MICBIAS Output Voltage VMICBIAS ILOAD = 1mA, TA = +25°C 1.5 1.55 1.6 V
Load Regulation ILOAD = 1mA to 2mA 0.2 10 mV
VRIPPLE = 100mVP-P at 217Hz 82 dB
MICBIAS Line Ripple Rejection LRR VRIPPLE = 100mVP-P at 10kHz 81 dB
MICBIAS Noise Voltage A-weighted 9.5 µVRMS
AUTOMATIC GAIN CONTROL
AGC Hold Duration AGCHLD[1:0] setting range, FREQ ≠ 0 50 400 ms
AGC Attack Time AGCATK[1:0] setting range, FREQ ≠ 0 3 200 ms
AGC Release Time AGCRLS[2:0] setting range, FREQ ≠ 0 0.078 10 s
AGC Threshold Level AGCSTH[3:0] setting range, FREQ ≠ 0 -3 -18 dB
NOISE GATE
NG Attack and Release Time 0.5 s
NG Threshold Level -72 -16 dB
Noise Gate Threshold Step Size 4dB
NG Attenuation 012dB
DIGITAL SIDETONE
Sidetone Gain Adjust DVST 2dB steps -60 0 dB
8kHz 2.2
Sidetone Phase Delay PDLY
MIC input to headphone
output, f = 1kHz, HP filter
disabled 16kHz 1.1
ms
MAX9860
16-Bit Mono Audio Voice Codec
_______________________________________________________________________________________ 7
DIGITAL AUDIO INTERFACE ELECTRICAL CHARACTERISTICS
(VDVDD = VDVDDIO = 1.8V, unless otherwise noted.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
BCLK Cycle Time tBCLKS Slave operation 75 ns
BCLK High Time tBCLKH Slave operation 30 ns
BCLK Low Time tBCLKL Slave operation 30 ns
BCLK or LRCLK Rise and Fall
Time tR, tFMaster operation 7 ns
SDIN or LRCLK to BCLK Rising
Setup Time tSU ABCI = DBCI = 0 25 ns
SDIN or LRCLK to BCLK Falling
Setup Time tSU ABCI = DBCI = 1 25 ns
SDIN or LRCLK to BCLK Rising
Hold Time tHD ABCI = DBCI = 0 0 ns
SDIN or LRCLK to BCLK Falling
Hold Time tHD ABCI = DBCI = 1 0 ns
SDOUT Delay Time from BCLK
Rising Edge tDLY ABCI = DBCI = 0, CL = 30pF 0 40 ns
I2C INTERFACE ELECTRICAL CHARACTERISTICS
(VDVDD = VDVDDIO = 1.8V, unless otherwise noted.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Serial-Clock Frequency fSCL 0 400 kHz
Bus Free Time Between STOP
and START Conditions tBUF 1.3 µs
Hold Time (Repeated) START
Condition tHD
,
STA 0.6 µs
SCL Pulse Width Low tLOW 1.3 µs
SCL Pulse Width High tHIGH 0.6 µs
Setup Time for a Repeated
START Condition tSU,STA 0.6 µs
Data Hold Time tHD
,
DAT 0 900 ns
Data Setup Time tSU
,
DAT 100 ns
SDA and SCL Receiving
Rise Time tRCB is in pF 20 + 0.1CB300 ns
SDA and SCL Receiving
Fall Time tFCB is in pF 20 + 0.1CB300 ns
MAX9860
16-Bit Mono Audio Voice Codec
8 _______________________________________________________________________________________
Note 2: All devices are 100% production tested at room temperature. All temperature limits are guaranteed by design.
Note 3: Supply current measurements taken with no applied signal at microphone inputs. A digital zero audio signal used for all dig-
ital serial audio inputs. Headphone outputs are loaded as stated in the global conditions.
Note 4: DAC performance is measured at headphone outputs.
Note 5: ADC, DAC, and headphone amplifier dynamic ranges are measured using the EIAJ method. -60dBV 1kHz input signal, A-weight-
ed and normalized to 0dBFS.
Note 6: Notch for GSM filters occurs at 217Hz.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SDA Transmitting
Fall Time tFCB is in pF 20 + 0.1CB250 ns
Setup Time for STOP Condition tSU
,
STO 0.6 µs
Bus Capacitance CB400 pF
Pulse Width of Suppressed Spike tSP 050ns
DIGITAL INPUTS (LRCLK, BCLK, SDIN, MCLK)
Input Voltage High VIH 0.7
x DVDDIO V
Input Voltage Low VIL 0.3
x DVDDIO V
MCLK Input Voltage High 1.4 V
MCLK Input Voltage Low 0.4 V
Input Leakage Current IIH, IIL TA = +25°C -1 +1 µA
Input Capacitance 3pF
DIGITAL INPUTS (SCL, SDA)
Input Voltage High VIH 0.7
x DVDD V
Input Voltage Low VIL 0.3
x DVDD V
Input Hysteresis 200 mV
Input Leakage Current IIH, IIL TA = +25oC-1+1µA
Input Capacitance 3pF
CMOS DIGITAL OUTPUTS (BCLK, LRCLK, SDOUT)
Output Low Voltage VOL IOL = 3mA 0.4 V
Output High Voltage VOH IOL = 3mA DVDDIO
- 0.4 V
OPEN-DRAIN DIGITAL OUTPUTS (SDA, IRQ)
Output High Leakage Current IOH VOUT = DVDDIO, TA = +25°C -1 +1 µA
Output Low Voltage VOL IOL = 3mA 0.4 V
I2C INTERFACE ELECTRICAL CHARACTERISTICS (continued)
(VDVDD = VDVDDIO = 1.8V, unless otherwise noted.) (Note 2)
MAX9860
16-Bit Mono Audio Voice Codec
_______________________________________________________________________________________
9
TOTAL HARMONIC DISTORTION + NOISE
vs. OUTPUT POWER (DAC TO HP)
MAX9860 toc01
OUTPUT POWER (mW)
THD+N (%)
252015105
0.01
0.1
1
10
0.001
030
RL = 32Ω
f = 3.5kHz
f = 1kHz
f = 20kHz
TOTAL HARMONIC DISTORTION + NOISE
vs. OUTPUT POWER (DAC TO HP)
MAX9860 toc02
OUTPUT POWER (mW)
THD+N (%)
5040302010
0.01
0.1
1
10
0.001
060
RL = 16Ω
f = 3.5kHz
f = 1kHz
f = 20kHz
TOTAL HARMONIC DISTORTION + NOISE
vs. FREQUENCY (DAC TO HP)
MAX9860 toc03
FREQUENCY (kHz)
THD+N (%)
10.1
0.01
0.1
1
10
0.001
0.01 10
RL = 32Ω
POUT = 5mW
POUT = 20mW
TOTAL HARMONIC DISTORTION + NOISE
vs. FREQUENCY (DAC TO HP)
MAX9860 toc04
FREQUENCY (kHz)
THD+N (%)
10.1
0.01
0.1
1
10
0.001
0.01 10
RL = 16Ω
POUT = 5mW
POUT = 20mW
TOTAL HARMONIC DISTORTION + NOISE
vs. FREQUENCY (MICL TO ADC)
MAX9860 toc05
FREQUENCY (kHz)
THD+N (%)
1010.1
0.01
0.1
1
10
0.001
0.01 100
MICPRE = 0dB
VIN = 1VP-P
TOTAL HARMONIC DISTORTION + NOISE
vs. FREQUENCY (MICL TO ADC)
MAX9860 toc06
FREQUENCY (kHz)
THD+N (%)
1010.1
0.1
1
10
0.01
0.01 100
MICPRE = +20dB
VIN = 100mVP-P
TOTAL HARMONIC DISTORTION + NOISE
vs. FREQUENCY (MICL TO ADC)
MAX9860 toc07
FREQUENCY (kHz)
THD+N (%)
1010.1
0.01
0.1
1
10
0.001
0.01 100
MICPRE = +30dB
VIN = 31VP-P
HEADPHONE OUTPUT POWER
vs. LOAD RESISTANCE
MAX9860 toc08
LOAD RESISTANCE (Ω)
OUTPUT POWER (mW)
125100755025
10
20
30
40
50
60
0
0150
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (DAC TO HP)
MAX9860 toc09
FREQUENCY (kHz)
PSRR (dB)
1010.1
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
-120
0.01 100
Typical Operating Characteristics
(VAVDD = +1.8V, VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF,
CPREG = CREG = 1µF, CMICBIAS = 1µF AVMICPGA = 0dB, AVPRE = +20dB, MCLK = 13MHz, TA= +25°C, unless otherwise noted.)
MAX9860
16-Bit Mono Audio Voice Codec
10 ______________________________________________________________________________________
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (MIC TO ADC)
MAX9860 toc10
FREQUENCY (kHz)
PSRR (dB)
1010.1
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
-120
0.01 100
0dBFS FFT (DAC TO HP)
MAX9860 toc11
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 13MHz
LRCLK = 8kHz
PLL DISABLED
-60dBFS FFT (DAC TO HP)
MAX9860 toc12
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 13MHz
LRCLK = 8kHz
PLL DISABLED
0dBFS FFT (DAC TO HP)
MAX9860 toc13
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 13MHz
LRCLK = 8kHz
PLL ENABLED
-60dBFS FFT (DAC TO HP)
MAX9860 toc14
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 13MHz
LRCLK = 8kHz
PLL ENABLED
0dBFS FFT (DAC TO HP AMP)
MAX9860 toc15
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 12.288MHz
LRCLK = 48kHz
PLL DISABLED
-60dBFS FFT (DAC TO HP AMP)
MAX9860 toc16
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 12.288MHz
LRCLK = 48kHz
PLL DISABLED
0dBFS FFT (MICL TO ADC)
MAX9860 toc17
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
321
-120
-100
-80
-60
-40
-20
0
20
-140
04
MCLK = 13MHz
LRCLK = 8kHz
PLL DISABLED
-60dBFS FFT (MICL TO ADC)
MAX9860 toc18
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
321
-120
-100
-80
-60
-40
-20
0
20
-140
04
MCLK = 13MHz
LRCLK = 8kHz
PLL DISABLED
Typical Operating Characteristics (continued)
(VAVDD = +1.8V, VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF,
CPREG = CREG = 1µF, CMICBIAS = 1µF AVMICPGA = 0dB, AVPRE = +20dB, MCLK = 13MHz, TA= +25°C, unless otherwise noted.)
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 11
0dBFS FFT (MICL TO ADC)
MAX9860 toc19
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
321
-120
-100
-80
-60
-40
-20
0
20
-140
04
MCLK = 13MHz
LRCLK = 8kHz
PLL ENABLED
-60dBFS FFT (MICL TO ADC)
MAX9860 toc20
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
321
-120
-100
-80
-60
-40
-20
0
20
-140
04
MCLK = 13MHz
LRCLK = 8kHz
PLL ENABLED
0dBFS FFT (MICL TO ADC)
MAX9860 toc21
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 12.288MHz
LRCLK = 48kHz
PLL DISABLED
-60dBFS FFT (MICL TO ADC)
MAX9860 toc22
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
15105
-120
-100
-80
-60
-40
-20
0
20
-140
020
MCLK = 12.288MHz
LRCLK = 48kHz
PLL DISABLED
-5dBFS WIDEBAND FFT (DAC TO HP)
MAX9860 toc23
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
1000100101
-80
-60
-40
-20
0
20
-100
0.1 10,000
MCLK = 13MHz
LRCLK = 8kHz
PLL DISABLED
RL = 32Ω
-60dBFS WIDEBAND FFT (DAC TO HP)
MAX9860 toc24
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dB)
1000100101
-80
-60
-40
-20
0
20
-100
0.1 10,000
MCLK = 13MHz
LRCLK = 8kHz
PLL DISABLED
RL = 32Ω
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX9860 toc25
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
1.901.851.801.751.70
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0
1.65 1.95
IAVDD
IDVDD + IDVDDIO
FULL-DUPLEX 8kHz MODE
DAC DIGITAL FILTER
FREQUENCY RESPONSE, 8kHz
MAX9860 toc26
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dBFS)
10.1
-80
-70
-60
-50
-40
-30
-20
-10
0
10
-90
0.01 10
ELLIPTICAL FOR 8kHz GSM WITH
NOTCH AT 217Hz
ADC DIGITAL FILTER
FREQUENCY RESPONSE, 8kHz
MAX9860 toc27
FREQUENCY (kHz)
OUTPUT AMPLITUDE (dBFS)
10.1
-80
-70
-60
-50
-40
-30
-20
-10
0
10
-90
0.01 10
ELLIPTICAL FOR 8kHz GSM WITH
NOTCH AT 217Hz
Typical Operating Characteristics (continued)
(VAVDD = +1.8V, VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF,
CPREG = CREG = 1µF, CMICBIAS = 1µF AVMICPGA = 0dB, AVPRE = +20dB, MCLK = 13MHz, TA= +25°C, unless otherwise noted.)
MAX9860
16-Bit Mono Audio Voice Codec
12 ______________________________________________________________________________________
Typical Operating Characteristics (continued)
(VAVDD = +1.8V, VDVDD = VDVDDIO = +1.8V, RL= ∞, headphone load (RL) connected between OUTP and OUTN, CREF = 2.2µF,
CPREG = CREG = 1µF, CMICBIAS = 1µF AVMICPGA = 0dB, AVPRE = +20dB, MCLK = 13MHz, TA= +25°C, unless otherwise noted.)
HEADPHONE STARTUP WAVEFORM
MAX9860 toc28
TIME (4ms/div)
SPK+ -SPK-
(1V/div)
SDA
(2V/div)
HEADPHONE SHUTDOWN WAVEFORM
MAX9860 toc29
TIME (2ms/div)
SPK+ -SPK-
(1V/div)
SDA
(2V/div)
ADC OUTPUT
(500mV/div)
SDA
(2V/div)
SOFT-START ADC
MAX9860 toc30
TIME (4ms/div)
-80
-60
-70
-40
-50
-30
-20
0
-10
10
-100 -80-90 -60-70 -40-50 -20-30 0-10
AUTOMATIC GAIN CONTROL THRESHOLDS
MAX9860 toc31
INPUT AMPLITUDE (dBV)
OUTPUT AMPLITUDE (dBFS)
-90
-70
-80
-50
-60
-40
-30
-10
-20
0
-100 -80 -60 -40 -20
NOISE GATE THRESHOLDS
MAX9860 toc32
INPUT AMPLITUDE (dBV)
OUTPUT AMPLITUDE (dBFS)
DYNAMIC RANGE
vs. MCLK FREQUENCY, -60dBFS (DAC to HP)
MAX9860 toc34
MCLK FREQUENCY (MHz)
DYNAMIC RANGE (dB)
50403020
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
-120
10 60
LRCLK = 8kHz
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 13
Pin Description
PIN NAME FUNCTION
1 MICBIAS Microphone Bias. +1.55V microphone bias for internal and/or external microphone. An external resistor from
2.2kΩ to 470Ω should be used to set the microphone current. Bypass to MICGND with a 1µF capacitor.
2 REG Internal Bias. PREG/2 voltage reference. Bypass to AGND with a 1µF capacitor (+0.8V).
3 PREG Positive Internal Regulated Supply. Bypass to AGND with a 1µF capacitor (+1.6V).
4 REF Converter Reference (1.23V). Bypass to AGND with a 2.2µF capacitor.
5 AGND Analog Ground
6 AVDD Analog Power Supply. Bypass to AGND with 10µF and 0.1µF capacitors.
7 OUTP Positive Headphone Output
8 OUTN Negative Headphone Output
9 SDA I2C Serial-Data Input/Output
10 SCL I2C Serial-Data Clock
11 DVDDIO Digital Interface Power Supply. Supply for digital audio interface. Bypass to DGND with a 1µF capacitor.
12 DGND Digital Ground
13 DVDD Digital Core Power Supply. Bypass to DGND with a 1µF capacitor.
14 MCLK Master Clock Input
15 SDOUT Serial Audio Interface ADC Data Output
16 SDIN Serial Audio Interface DAC Data Input
17 LRCLK Serial Audio Interface Left/Right Clock
18 BCLK Serial Audio Interface Bit Clock
19 IRQ Interrupt Request. IRQ is an active-low open drain output. Pull up to DVDDIO with a 10kΩ resistor.
20 MICRN Negative Right Microphone Input. AC-couple to low-side of microphone or connect to negative signal.
AC-couple to ground for single-ended operation.
21 MICRP Positive Right Microphone Input. AC-couple to high-side of microphone or connect to positive signal.
AC-couple the signal for single-ended operation.
22 MICLN Negative Left Microphone Input. AC-couple to low-side of microphone or connect to negative signal.
AC-couple to ground for single-ended operation.
23 MICLP Positive Left Microphone Input. AC-couple to high-side of microphone or connect to positive signal.
AC-couple the signal for single-ended operation.
24 MICGND MICBIAS Ground. Connect to AGND.
— EP Exposed Pad. Connect to AGND.
MAX9860
Detailed Description
The MAX9860 is a low-power, voiceband, mono audio
codec designed to provide a complete audio solution
for wireless voice headsets and other mono audio
devices.
The mono playback path accepts digital audio over a
flexible digital audio interface compatible with I2S, TDM,
and left-justified audio signals. An oversampling sigma-
delta DAC converts an incoming digital data stream to
analog audio and outputs through the mono bridge-tied
load headphone amplifier.
The stereo record path has two microphone inputs with
selectable gain. The microphones are powered by an
integrated microphone bias. An oversampling sigma-
delta ADC converts the microphone signals and out-
puts the digital bit stream over the digital audio
interface.
The record path includes automatic gain control (AGC)
to optimize the signal level and a noise gate to reduce
idle noise. The automatic gain control monitors the out-
puts of the ADC and makes constant adjustments to the
input gain to reduce the dynamic range of the incoming
microphone signal by up to 20dB. The noise gate cor-
rects for the increase in noise typically associated with
AGC by lowering the gain when there is no audio signal.
Integrated digital filtering provides a range of notch and
highpass filters for both the playback and record paths
to limit undesirable low-frequency signals and GSM
transmission noise. The digital filtering provides attenu-
ation of out-of-band energy by up to 76dB, eliminating
audible aliasing. A digital sidetone function allows
audio from the record path to be summed into the play-
back path after digital filtering.
The MAX9860’s flexible clock circuitry utilizes a pro-
grammable clock divider and a digital PLL to allow the
DAC and ADC to operate at maximum dynamic range
for all combinations of master clock (MCLK) and sam-
ple rate (LRCLK). Any master clock between 10MHz to
60MHz is supported as are all sample rates from 8kHz
to 48kHz. Master and slave mode are supported for
maximum flexibility.
I2C Registers
The MAX9860 audio codec is completely controlled
through software using an I2C interface. The power-on
default setting is software shutdown, requiring that the
internal registers be programmed to activate the device.
See Table 1 for the device’s complete register map.
I
2
C Slave Address
The MAX9860 responds to the slave address 0x20 for
all write commands and 0x21 for all read operations.
16-Bit Mono Audio Voice Codec
14 ______________________________________________________________________________________
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 15
REGISTER B7 B6 B5 B4 B3 B2 B1 B0 REGISTER
ADDRESS POR R/W
STATUS/INTERRUPT
Interrupt Status CLD SLD ULK 0 0 0 0 0 0x00 — R
Microphone NG/AGC
Readback NG AGC 0x01 — R
Interrupt Enable ICLD ISLD IULK 0 0 0 0 0 0x02 0x00 R/W
CLOCK CONTROL
System Clock 0 0 PSCLK 0 FREQ 16KHZ 0x03 0x00 R/W
Stereo Audio Clock
Control High PLL NHI 0x04 0x00 R/W
Stereo Audio Clock
Control Low NLO 0x05 0x00 R/W
DIGITAL AUDIO INTERFACE
Interface MAS WCI DBCI DDLY HIZ TDM 0 0 0x06 0x00 R/W
Interface 0 0 ABCI ADLY ST BSEL 0x07 0x00 R/W
DIGITAL FILTERING
Voice Filter AVFLT DVFLT 0x08 0x00 R/W
DIGITAL LEVEL CONTROL
DAC Attenuation DVA 0x09 0x00 R/W
ADC Output Levels ADCRL ADCLL 0x0A 0x00 R/W
DAC Gain and
Sidetone 0 DVG DVST 0x0B 0x00 R/W
MICROPHONE LEVEL CONTROL
Microphone Gain 0 PAM PGAM 0x0C 0x00 R/W
RESERVED
Reserved 0 0 0 0 0 0 0 0 0x0D 0x00
MICROPHONE AUTOMATIC GAIN CONTROL
Microphone AGC AGCSRC AGCRLS AGCATK AGCHLD 0x0E 0x00 R/W
Noise Gate,
Microphone AGC ANTH AGCTH 0x0F 0x00 R/W
POWER MANAGEMENT
System Shutdown SHDN 0 0 0 DACEN 0 ADCLEN ADCREN 0x10 0x00 R/W
Table 1. I2C Register Map
MAX9860
Status/Interrupt
Status registers 0x00 and 0x01 are read-only registers
that report the status of various device functions. The
status register bits are cleared upon a read operation of
the status register and are set the next time the event
occurs. Register 0x02 determines whether or not the sta-
tus flags in register 0x00 simultaneously sets IRQ high.
16-Bit Mono Audio Voice Codec
16 ______________________________________________________________________________________
Table 2. Status/Interrupt Registers
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x00 CLD SLD ULK 0 0 0 0 0
0x01 NG AGC
0x02 ICLD ISLD IULK 0 0 0 0 0
BITS FUNCTION
CLD
Clip Detect Flag. Indicates that a signal has become clipped in the ADC or DAC digital signal paths. CLD also
indicates that the AGC function, when enabled, has set the microphone PGA to 0dB and no further gain reduction
is possible.
SLD Slew Level Detect Flag. When volume or gain changes are made, the slewing circuitry smoothly steps through all
intermediate settings. When SLD is set high, all slewing has completed and the volume or gain is at its final value.
ULK
Digital PLL Unlock Flag. Indicates that the digital audio PLL for the ADC or DAC has become unlocked and digital
signal data is not reliable. When beginning operation in master mode, this flag goes high and can be cleared by
reading the status register.
Noise Gate Attenuation. When the noise gate is enabled these bits indicate the current noise gate attenuation.
Code Attenuation
000 0dB
001 1dB
010 2dB
011 3dB
100 6dB
101 8dB
110 10dB
NG
111 12dB
AGC AGC Gain. When the AGC is enabled these bits indicate the AGC controlled level to the MIC preamp. The levels
indicated by these bits correspond to the levels defined for the PGAM bits described in register 0x0C.
Clock Control
The MAX9860 can work with a master clock (MCLK)
supplied from any system clock within the range of
10MHz to 60MHz. Internally, the MAX9860 requires a
10MHz to 20MHz clock so a prescaler divides by 1, 2,
or 4 to create the internal clock (PCLK). PCLK is used
to clock all portions of the MAX9860.
The MAX9860 is capable of supporting any sample rate
from 8kHz to 48kHz, including all common sample rates
(8kHz, 16kHz, 24kHz, 32kHz, 44.1kHz, 48kHz). To
accommodate a wide range of system architectures,
the MAX9860 supports three main clocking modes:
Normal Mode: This mode uses a 15-bit clock divider
coefficient to set the sample rate relative to the
prescaled MCLK input (PCLK). This allows high flexibili-
ty in both the MCLK and LRCLK frequencies and can
be used in either master or slave mode.
Exact Integer Mode: Common MCLK frequencies
(12MHz, 13MHz, and 19.2MHz) can be programmed to
operate in exact integer mode for both 8kHz and 16kHz
sample rates. In these modes, the MCLK and LRCLK
rates are selected by using the FREQ and 16KHZ bits
instead of the NHI, NLO, and PLL control bits.
PLL Mode: When operating in slave mode, a PLL can
be enabled to lock onto externally generated LRCLK
signals that are asynchronously related to PCLK.
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 17
Table 3. Clock Control Registers
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x03 0 0 PSCLK 0 FREQ 16KHZ
0x04 PLL NHI
0x05 NLO
BITS FUNCTION
PSCLK[1:0]
MCLK Prescaler
Divides MCLK down to generate a PCLK between 10MHz and 20MHz.
00 = Disable clock for low-power shutdown.
01 = Select if MCLK is between 10MHz and 20MHz.
10 = Select if MCLK is between 20MHz and 40MHz.
11 = Select if MCLK is greater than 40MHz.
FREQ[1:0]
Integer Clock Mode
Enables exact integer mode for three predefined PCLK frequencies. Exact integer mode is normally
intended for master mode, but can be enabled in slave mode if the externally supplied LRCLK exactly
matches the frequency specified in each mode.
00 = Normal operation (configure clocking with the PLL, NHI, and NLO bits).
01 = Select when PCLK is 12MHz (LRCLK = PCLK/1500 or PCLK/750).
10 = Select when PCLK is 13MHz (LRCLK = PCLK/1625 or PCLK/812.5).
11 = Select when PCLK is 19.2MHz (LRCLK = PCLK/2400 or PCLK/1200).
When FREQ ≠ 00, the PLL, NHI, and NLO bits are unused.
16KHZ
16kHz Mode
When FREQ ≠ 00:
0 = LRCLK is exactly 8kHz.
1 = LRCLK is exactly 16kHz.
When FREQ = 00, 16KHZ is used to set the AGC clock rate:
0 = Use when LRCLK ≤ 24kHz.
1 = Use when LRCLK > 24kHz.
MAX9860
16-Bit Mono Audio Voice Codec
18 ______________________________________________________________________________________
Table 3. Clock Control Registers (continued)
BITS FUNCTION
PLL
PLL Enable
0 = (Valid for slave and master mode)—The frequency of LRCLK is set by the NHI and NLO divider
bits. Set PLL = 0 in slave mode only if the externally generated LRCLK can be exactly selected
using the LRCLK divider.
1 = (Valid for slave mode only)—Used when the audio master generates an LRCLK not selectable
using the LRCLK divider. A digital PLL locks on to the externally supplied LRCLK signal
regardless of the MCLK frequency.
Rapid Lock Mode
To enable rapid lock mode set NHI and NLO to the nearest desired ratio and set NLO[0] = 1 (Register
0x05, bit 0) before setting the PLL mode bit.
NHI and NLO
LRCLK Divider
NHI and NLO control a 15-bit clock divider (N). When the PLL = 0 and FREQ = 00, the frequency of
LRCLK is determined by the clock divider. See Table 4 for common N values.
N = (65,536 x 96 x fLRCLK)/fPCLK
fLRCLK = LRCLK frequency
fPCLK = prescaled MCLK internal clock frequency (PCLK)
LRCLK (kHz)
MCLK
(MHz) PSCLK 8 16 32 44.1 48
11.2896 01 116A 22D4 45A9 6000 687D
12 01 1062 20C5 4189 5A51 624E
12.288 01 1000 2000 4000 5833 6000
13 01 F20 1E3F 3C7F 535F 5ABE
19.2 01 A3D 147B 28F6 3873 3D71
24 10 1062 20C5 4189 5A51 624E
26 10 F20 1E3F 3C7F 535F 5ABE
27 10 E90 1D21 3A41 5048 5762
Table 4. Common N Values
Note: Values in bold italics are exact integers that provide
maximum full-scale performance.
Digital Audio Interface
The MAX9860’s digital audio interface supports a wide
range of operating modes to ensure maximum compati-
bility. See Figures 1 through 4 for timing diagrams. In
master mode, the MAX9860 outputs LRCLK and BCLK,
while in slave mode, they are inputs. When operating in
master mode, BCLK can be configured in a number of
ways to ensure compatiblity with other audio devices.
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 19
Table 5. Digital Audio Interface Registers
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x06 MAS WCI DBCI DDLY HIZ TDM 0 0
0x07 0 0 ABCI ADLY ST BSEL
BITS FUNCTION
MAS
Master Mode
0 = The MAX9860 operates in slave mode with LRCLK and BCLK configured as inputs.
1 = The MAX9860 operates in master mode with LRCLK and BCLK configured as outputs.
WCI
LRCLK Invert
0 = Left-channel data is input and output while LRCLK is low.
1 = Right-channel data is input and output while LRCLK is low.
WCI is ignored when TDM = 1.
DBCI
DAC BCLK Invert (must be set to ABCI)
In master and slave mode:
0 = SDIN is latched into the part on the rising edge of BCLK.
1 = SDIN is latched into the part on the falling edge of BCLK.
In master mode:
0 = LRCLK changes state following the rising edge of BCLK.
1 = LRCLK changes state following the falling edge of BCLK.
DDLY
DAC Delay Mode
0 = SDIN data is latched on the first BCLK edge following an LRCLK edge.
1 = SDIN data is assumed to be delayed one BCLK cycle so that it is latched on the 2nd BCLK edge
following an LRCLK edge (I2S-compatible mode).
DDLY is ignored when TDM = 1.
HIZ
SDOUT High-Impedance Mode
0 = SDOUT is set either high or low after all data bits have been transferred out of the part.
1 = SDOUT goes to a high-impedance state after all data bits have been transferred out of the part,
allowing SDOUT to be shared by other devices.
Use HIZ only when TDM = 1.
TDM
TDM Mode Select
0 = LRCLK signal polarity indicates left and right audio.
1 = LRCLK is a framing pulse which transitions polarity to indicate the start of a frame of audio data
consisting of multiple channels.
W hen op er ati ng i n TD M m od e the l eft channel i s outp ut i m m ed i atel y fol l ow i ng the fr am e sync p ul se. If r i g ht-
channel d ata i s b ei ng tr ansm i tted , the 2nd channel of d ata i m m ed i atel y fol l ow s the 1st channel d ata.
ABCI
ADC BCLK Invert (must be set to DBCI)
0 = SDOUT is valid on the rising edge of BCLK and transitions immediately after the rising edge.
1 = SDOUT is valid on the falling edge of BCLK and transitions immediately after the falling edge.
MAX9860
16-Bit Mono Audio Voice Codec
20 ______________________________________________________________________________________
Table 5. Digital Audio Interface Registers (continued)
BITS FUNCTION
ADLY
ADC Delay Mode
0 = SDOUT data is valid on the first BCLK edge following an LRCLK edge.
1 = SDOUT data is delayed one BCLK cycle so that it is valid on the 2nd BCLK edge following an
LRCLK edge (I2S-compatible mode).
ADLY is ignored when TDM = 1.
ST
Stereo Enable
0 = The interface transmits and receives only one channel of data. If right record path is enabled, no
data from this channel is transmitted.
1 = The interface operates in stereo. The left and right incoming data are summed to mono and then
routed to the DAC. The summed data is divided by 2 to prevent overload. Both the left and right
record signals are transmitted.
BSEL
BCLK Select
Configures BCLK when operating in master mode. BSEL has no effect in slave mode. Set BSEL = 010,
unless sharing the bus with multiple devices.
000 = Off
001 = 64x LRCLK (192x internal clock divided by 3)
010 = 48x LRCLK (192x internal clock divided by 4)
011 = Reserved for future use.
100 = PCLK/2
101 = PCLK/4
110 = PCLK/8
111 = PCLK/16
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 21
LEFT
LEFT JUSTIFIED : WCI = 0, _BCI = 0, _DLY = 0
AUDIO MASTER MODES (ST = 1):
LEFT JUSTIFIED + LRCLK INVERT: WCI = 1, _BCI = 0, _DLY = 0
LEFT JUSTIFIED + BCLK INVERT: WCI = 0, _BCI = 1, _DLY = 0
I2S: WCI = 0, _BCI = 0, _DLY = 1
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0D15D15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
RELATIVE TO PCLK (NOTE 7)
RIGHT
RIGHT
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0D15D15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
RELATIVE TO PCLK (NOTE 7)
LEFT
LEFT
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0D15D15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
RELATIVE TO PCLK (NOTE 7)
RIGHT
LEFT
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0D15D15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
RELATIVE TO PCLK (NOTE 7)
RIGHT
D0
D15
D15
D15
D15
D15
D15
D15
NOTE 7: THE DELAY FROM A BCLK EDGE AND AN LRCLK EDGE IS DETERMINED BY LENGTH OF TIME THAT PCLK (THE INTERNALLY DIVIDED DOWN VERSION OF MCLK AS DEFINED BY THE PSCLK BITS) IS HIGH DURING
ONE PERIOD OF MCLK PLUS THE INTERNAL DELAY. FOR EXAMPLE: IF PCLK = 12.288MHz, THE DELAY BETWEEN BCLK AND LRCLK IS TYPICALLY 45ns.
D15 D0
Figure 1. Digital Audio Interface Audio Master Mode Examples
MAX9860
16-Bit Mono Audio Voice Codec
22 ______________________________________________________________________________________
VOICE (TDM) MASTER MODES:
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
L15
RELATIVE TO PCLK (NOTE 8)
_BCI = 0, HIZ = 1, ST = 0
_BCI = 1, HIZ = 1, ST = 0
_BCI = 0, HIZ = 0, ST = 0
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
L15
RELATIVE TO PCLK (NOTE 8)
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
L15
RELATIVE TO PCLK (NOTE 8)
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
1/fS
CONFIGURED BY BSEL
7ns (typ)
7ns (typ)
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min)
7ns (typ)
7ns (typ)
0ns (min)
40ns (max)
0ns (min)
L15
RELATIVE TO PCLK (NOTE 8)
_BCI = 0, HIZ = 1, ST = 1
R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0R15
R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0R15
NOTE 8: THE DELAY FROM A BCLK EDGE AND AN LRCLK EDGE IS DETERMINED BY LENGTH OF TIME THAT PCLK (THE INTERNALLY DIVIDED DOWN VERSION OF MCLK AS DEFINED BY THE PSCLK BITS) IS HIGH DURING
ONE PERIOD OF MCLK PLUS THE INTERNAL DELAY. FOR EXAMPLE: IF PCLK = 12.288MHz, THE DELAY BETWEEN BCLK AND LRCLK IS TYPICALLY 45ns.
Figure 2. Digital Audio Interface Voice Master Mode Examples
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 23
LEFT
AUDIO SLAVE MODES (ST = 1):
LEFT JUSTIFIED: WCI = 0, _BCI = 0, _DLY = 0
LEFT JUSTIFIED + LRCLK INVERT: WCI = 1, _BCI = 0, _DLY = 0
LEFT JUSTIFIED + BCLK INVERT: WCI = 0, _BCI = 1, _DLY = 0
I2S: WCI = 0, _BCI = 0, _DLY = 1
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
1/fS
75ns (min)
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0D15
D15
25ns (min) 0ns (min)
40ns (max)
0ns (min)
RIGHT
RIGHT
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
1/fS
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0D15
D15
25ns (min) 0ns (min)
40ns (max)
0ns (min)
LEFT
LEFT
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
1/fS
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15D15
25ns (min) 0ns (min)
40ns (max)
0ns (min)
RIGHT
LEFT
LRCLK
BCLK
SDOUT
SDIN
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1
1/fS
D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0D15
D15
25ns (min) 0ns (min)
RIGHT
D15D15
D15
D15
D15
D15
30ns (min)
30ns (min)
25ns (min)
75ns (min)
30ns (min)
25ns (min)
75ns (min)
30ns (min)
25ns (min)
75ns (min)
30ns (min)
25ns (min)
0ns (min)
0ns (min)
0ns (min)
0ns (min)
40ns (max)
0ns (min)
D15 D0 D15 D0
Figure 3. Digital Audio Interface Audio Slave Mode Examples
MAX9860
16-Bit Mono Audio Voice Codec
24 ______________________________________________________________________________________
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
1/fS
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min) 0ns (min)
40ns (max)
0ns (min)
L15
VOICE (TDM) SLAVE MODES: _BCI = 0, HIZ =1, ST = 0
_BCI = 1, HIZ = 1, ST = 0
_BCI = 0, HIZ = 0, ST = 0
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min) 0ns (min)
40ns (max)
0ns (min)
L15
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min) 0ns (min)
40ns (max)
0ns (min)
L15
75ns (min)
30ns (min)
25ns (min)
75ns (min)
30ns (min)
75ns (min)
30ns (min)
0ns (min)
0ns (min)
1/fS
25ns (min) 0ns (min)
0ns (min)
1/fS
25ns (min) 0ns (min)
0ns (min)
LRCLK
BCLK
SDOUT
SDIN
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0
1/fS
L14 L13 L12 L11 L10 L9 L8 L7 L6 L5 L4 L3 L2 L1 L0L15
25ns (min) 0ns (min)
40ns (max)
0ns (min)
L15
_BCI = 0, HIZ = 1, ST = 1
75ns (min)
30ns (min)
25ns (min) 0ns (min)
0ns (min)
R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0R15
R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0R15
Figure 4. Digital Audio Interface Voice Slave Mode Examples
Digital Filtering
The MAX9860 incorporates selecable highpass and
notch filters for both the playback and record paths.
Each filter is valid for a specific sample rate.
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 25
Table 6. Digital Filter Registers
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x08 AVFLT DVFLT
BITS FUNCTION
AVFLT ADC Voice Filter Frequency Select. See Table 7.
DVFLT DAC Voice Filter Frequency Select. See Table 7.
Table 7. Digital Filters
CODE FILTER TYPE SAMPLE RATE DESCRIPTION
0x0 — — Disabled
0x1 Elliptical 16kHz Elliptical highpass with 217Hz notch
0x2 Butterworth 16kHz 500Hz Butterworth highpass
0x3 Elliptical 8kHz Elliptical highpass with 217Hz notch
0x4 Butterworth 8kHz 500Hz Butterworth highpass
0x5 Butterworth 48kHz 200Hz Butterworth highpass
0x6 to 0xF — — Reserved
MAX9860
Digital Level Control
The MAX9860 includes digital gain adjustment for the
playback and record paths. Independent gain
adjustment is provided for the two record channels.
Sidetone gain adjustment is also provided to set the
sidetone level relative to the playback level.
16-Bit Mono Audio Voice Codec
26 ______________________________________________________________________________________
Table 8. Digital Level Control Registers
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x09 DVA
0x0A ADCRL ADCLL
0x0B 0 DVG DVST
BITS FUNCTION
DAC Level Adjust
Adjusts the digital audio level before being converted by the DAC. The least significant bit of DVA is
always 0.
CODE GAIN CODE GAIN CODE GAIN
0x00 +3 0x40 -29 0x80 -61
0x02 +2 0x42 -30 0x82 -62
0x04 +1 0x44 -31 0x84 -63
0x06 0 0x46 -32 0x86 -64
0x08 -1 0x48 -33 0x88 -65
0x0A -2 0x4A -34 0x8A -66
0x0C -3 0x4C -35 0x8C -67
0x0E -4 0x4E -36 0x8E -68
0x10 -5 0x50 -37 0x90 -69
0x12 -6 0x52 -38 0x92 -70
0x14 -7 0x54 -39 0x94 -71
0x16 -8 0x56 -40 0x96 -72
0x18 -9 0x58 -41 0x98 -73
0x1A -10 0x5A -42 0x9A -74
0x1C -11 0x5C -43 0x9C -75
0x1E -12 0x5E -44 0x9E -76
0x20 -13 0x60 -45 0xA0 -77
0x22 -14 0x62 -46 0xA2 -78
0x24 -15 0x64 -47 0xA4 -79
0x26 -16 0x66 -48 0xA6 -80
0x28 -17 0x68 -49 0xA8 -81
0x2A -18 0x6A -50 0xAA -82
0x2C -19 0x6C -51 0xAC -83
0x2E -20 0x6E -52 0xAE -84
0x30 -21 0x70 -53 0xB0 -85
0x32 -22 0x72 -54 0xB2 -86
0x34 -23 0x74 -55 0xB4 -87
0x36 -24 0x76 -56 0xB6 -88
0x38 -25 0x78 -57 0xB8 -89
0x3A -26 0x7A -58 0xBA -90
0x3C -27 0x7C -59 ≥ 0xBC MUTE
DVA
0x3E -28 0x7E -60 — —
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 27
Table 8. Digital Level Control Registers (continued)
BITS FUNCTION
Left and Right ADC Output Level
Adjusts the digital audio level output by the ADCs.
CODE GAIN
0x0 +3
0x1 +2
0x2 +1
0x3 0
0x4 -1
0x5 -2
0x6 -3
0x7 -4
0x8 -5
0x9 -6
0xA -7
0xB -8
0xC -8
0xD -10
0xE -11
ADCRL/ADCLL
0xF -12
DAC Gain
The gain set by DVG adds to the level set by DVA.
CODE GAIN
00 0
01 +6
10 +12
DVG
11 +18
Sidetone
Sets the level of left ADC output mixed into the DAC.
CODE GAIN CODE GAIN
0x00 Disabled 0x10 -30
0x01 0 0x11 -32
0x02 -2 0x12 -34
0x03 -4 0x13 -36
0x04 -6 0x14 -38
0x05 -8 0x15 -40
0x06 -10 0x16 -42
0x07 -12 0x17 -44
0x08 -14 0x18 -46
0x09 -16 0x19 -48
0x0A -18 0x1A -50
0x0B -20 0x1B -52
0x0C -22 0x1C -54
0x0D -24 0x1D -56
0x0E -26 0x1E -58
DVST
0x0F -28 0x1F -60
MAX9860
Microphone Inputs
The MAX9860 provides two differential microphone
inputs and a low-noise 1.55V microphone bias for power-
ing the microphones. In typical applications, the left
microphone is used to record a voice signal and the
right microphone is used to record a background noise
signal. In applications that require only one microphone,
use the left microphone input and disable the right ADC.
The microphone signals are amplified by two stages of
gain and then routed to the ADCs. The first stage offers
selectable 0dB, 20dB, or 30dB settings. The second
stage is a programmable gain amplifier (PGA) adjustable
from 0dB to 20dB in 1dB steps. Zero-crossing detection
is included on the PGA to minimize zipper noise while
making gain changes. See Figure 5 for a detailed dia-
gram of the microphone input structure.
16-Bit Mono Audio Voice Codec
28 ______________________________________________________________________________________
MICLN
MICLP
MICBIAS
AGC
PGA
PGA
-
PREAMP
MICRN
ADC
L
ADC
R
MICRP
REG
1.55V
0/20/30dB
0dB to +20dB
0dB to +20dB
VCM
VCM
0/20/30dB
MICGND
PREAMP
MAX9860
Figure 5. Microphone Input Block Diagram
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 29
Table 9. Microphone Input Register
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x0C 0 PAM PGAM
BITS FUNCTION
Left and Right Microphone Preamp Gain
CODE GAIN (dB)
00 Disabled
01 0
10 +20
11 +30
PAM
Note: Selecting 00 disables the microphone inputs and microphone bias automatically.
Left and Right Microphone PGA
CODE GAIN (dB) CODE GAIN (dB)
0x00 +20 0x0B +9
0x01 +19 0x0C +8
0x02 +18 0x0D +7
0x03 +17 0x0E +6
0x04 +16 0x0F +5
0x05 +15 0x10 +4
0x06 +14 0x11 +3
0x07 +13 0x12 +2
0x08 +12 0x13 +1
0x09 +11 ≥ 0x14 0
0x0A +10 — —
PGAM
Note: When AGC is enabled, the AGC controller overrides these settings.
MAX9860
Automatic Gain Control (AGC)
and Noise Gate
The MAX9860 includes AGC on both microphone
inputs. AGC is enabled by setting the hold time through
AGCHLD. AGC dynamically controls the analog PGA
microphone input gain to hold the level constant over a
20dB input range, enhancing the voice path operation
for various use conditions. When AGC is enabled, it
monitors the signal level at the output of the ADC and
then makes gain adjustments by controlling the analog
microphone PGA. When AGC is enabled, PGAM is not
user programmable.
Since AGC increases the level of all signals below a
user-defined threshold, the noise floor effectively is
increased by 20dB. To counteract this, a noise gate is
included to reduce the gain at low levels. Unlike typical
noise gates that completely silence the output below a
threshold, the noise gate in the MAX9860 reduces the
gain for signals below the defined level. As the signal
level becomes further below the threshold, the gain is
further reduced. The Automatic Gain Control
Thresholds and Noise Gate Thresholds graphs in the
Typical Operating Characteristics
show the resulting
steady-state transfer curves when AGC and the noise
gate are enabled.
16-Bit Mono Audio Voice Codec
30 ______________________________________________________________________________________
Table 10. AGC and Noise Gate Registers
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x0E AGCSRC AGCRLS AGCATK AGCHLD
0x0F ANTH AGCTH
BITS FUNCTION
AGCSRC
AGC/Noise Gate Signal Source Select
0 = The left ADC output is used by the AGC and noise gate.
1 = The sum of the left and right ADC outputs is used by the AGC and noise gate.
AGC Release Time
Time taken by the AGC circuit to increase the gain from minimum to maximum.
CODE TIME
000 78ms
001 156ms
010 312ms
011 625ms
100 1.25s
101 2.5s
110 5s
AGCRLS
111 10s
AGC Attack Time
The time constant of the AGC gain reduction curve.
CODE TIME (ms)
00 3
01 12
10 50
AGCATK
11 200
AGC Hold Time
Time the AGC circuit waits before beginning to increase gain when a signal below the threshold is
detected.
CODE TIME (ms)
00 AGC disabled
01 50
10 100
AGCHLD
11 400
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 31
Table 10. AGC and Noise Gate Registers (continued)
BITS FUNCTION
Noise Gate Threshold
The signal level at which the noise gate begins reducing the gain. When the signal level is above the
threshold the noise gate has no effect. When the signal level is below the threshold, the noise gate
decreases the gain by 1dB for every 2dB the signal is below the threshold.
The noise gate can be enabled independently from AGC. When AGC is enabled, PGAM must be set to
+20dB (indicating a small signal is present) for the noise gate to attenuate.
For microphone signals, use the noise gate and AGC simultaneously with ANTH set between -16dB
and -28dB.
ANTH[3:0] LEVEL (dBFS) ANTH[3:0] LEVEL (dBFS)
0x0 Disabled 0x8 -44
0x1 -72 0x9 -40
0x2 -68 0xA -36
0x3 -64 0xB -32
0x4 -60 0xC -28
0x5 -56 0xD -24
0x6 -52 0xE -20
ANTH
0x7 -48 0xF -16
AGC Signal Threshold
The target output signal level. When the signal level is below the threshold, the AGC increases the
gain. The signal level is measured after ADCRL and ADCLL are applied to the ADC output.
ANTH[3:0] LEVEL (dBFS) ANTH[3:0] LEVEL (dBFS)
0x0 -3 0x8 -11
0x1 -4 0x9 -12
0x2 -5 0xA -13
0x3 -6 0xB -14
0x4 -7 0xC -15
0x5 -8 0xD -16
0x6 -9 0xE -17
AGCTH
0x7 -10 0xF -18
MAX9860
Power Management
The MAX9860 includes complete power management
control to minimize power usage. The DAC and both
ADCs can be independently enabled so that only the
required circuitry is active.
16-Bit Mono Audio Voice Codec
32 ______________________________________________________________________________________
Table 11. Power Management Register
REGISTER ADDRESS B7 B6 B5 B4 B3 B2 B1 B0
0x10 SHDN 0 0 0 DACEN 0 ADCLEN ADCREN
BITS FUNCTION
SHDN
Active-Low Software Shutdown
0 = MAX9860 is in full shutdown.
1 = MAX9860 is powered on.
When SHDN = 0. All register settings are preserved and the I2C interface remains active.
DACEN
DAC Enable
0 = DAC disabled.
1 = DAC enabled.
ADCLEN/ADCREN
ADC Left/Right Enable
0 = Left/right ADC disabled.
1 = Left/right ADC enabled.
The left ADC must be enabled when using the right ADC.
Revision Code
The MAX9860 includes a revision code to allow easy
identification of the device revision. The current revision
code is 0x40.
Table 12. Revision Code Register
ADDR B7 B6 B5 B4 B3 B2 B1 B0
0xFF REV
I
2
C Serial Interface
The MAX9860 features an I2C/SMBus™-compatible,
2-wire serial interface consisting of a serial-data line
(SDA) and a serial-clock line (SCL). SDA and SCL facili-
tate communication between the MAX9860 and the
master at clock rates up to 400kHz. Figure 6 shows the
2-wire interface timing diagram. The master generates
SCL and initiates data transfer on the bus. The master
device writes data to the MAX9860 by transmitting the
proper slave address followed by the register address
and then the data word. Each transmit sequence is
framed by a START (S) or REPEATED START (Sr) con-
dition and a STOP (P) condition. Each word transmitted
to the MAX9860 is 8 bits long and is followed by an
acknowledge clock pulse. A master reading data from
the MAX9860 transmits the proper slave address fol-
lowed by a series of nine SCL pulses. The MAX9860
transmits data on SDA in sync with the master-generat-
ed SCL pulses. The master acknowledges receipt of
each byte of data. Each read sequence is framed by a
START or REPEATED START condition, a not acknowl-
edge, and a STOP condition. SDA operates as both an
input and an open-drain output. A pullup resistor, typi-
cally greater than 500Ω, is required on SDA. SCL oper-
ates only as an input. A pullup resistor, typically greater
than 500Ω, is required on SCL if there are multiple mas-
ters on the bus, or if the single master has an open-
drain SCL output. Series resistors in line with SDA and
SCL are optional. Series resistors protect the digital
inputs of the MAX9860 from high voltage spikes on the
bus lines, and minimize crosstalk and undershoot of the
bus signals.
SMBus is a trademark of Intel Corp.
Bit Transfer
One data bit is transferred during each SCL cycle. The
data on SDA must remain stable during the high period
of the SCL pulse. Changes in SDA while SCL is high
are control signals (see the
START and STOP
Conditions
section).
START and STOP Conditions
SDA and SCL idle high when the bus is not in use.
A master initiates communication by issuing a START (S)
condition. A START condition is a high-to-low transition
on SDA with SCL high. A STOP (P) condition is a low-to-
high transition on SDA while SCL is high (Figure 7). A
START condition from the master signals the beginning
of a transmission to the MAX9860. The master terminates
transmission, and frees the bus, by issuing a STOP con-
dition. The bus remains active if a REPEATED START
(Sr) condition is generated instead of a STOP condition.
Early STOP Conditions
The MAX9860 recognizes a STOP condition at any
point during data transmission except if the STOP con-
dition occurs in the same high pulse as a START condi-
tion. For proper operation, do not send a STOP
condition during the same SCL high pulse as the
START condition.
Slave Address
The slave address is defined as the seven most signifi-
cant bits (MSBs) followed by the read/write bit. For the
MAX9860, the seven most significant bits are 0010000.
Setting the read/write bit to 1 (slave address = 0x21)
configures the MAX9860 for read mode. Setting the
read/write bit to 0 (slave address = 0x20) configures
the MAX9860 for write mode. The address is the first
byte of information sent to the MAX9860 after the
START condition.
Acknowledge
The acknowledge bit (ACK) is a clocked 9th bit that the
MAX9860 uses to handshake receipt each byte of data
when in write mode (see Figure 8). The MAX9860 pulls
down SDA during the entire master-generated 9th clock
pulse if the previous byte is successfully received.
Monitoring ACK allows for detection of unsuccessful
data transfers. An unsuccessful data transfer occurs if
a receiving device is busy or if a system fault has
occurred. In the event of an unsuccessful data transfer,
the bus master retries communication. The master pulls
down SDA during the 9th clock cycle to acknowledge
receipt of data when the MAX9860 is in read mode. An
acknowledge is sent by the master after each read byte
to allow data transfer to continue. A not acknowledge is
sent when the master reads the final byte of data from
the MAX9860, followed by a STOP condition.
Write Data Format
A write to the MAX9860 includes transmission of a
START condition, the slave address with the R/Wbit set
to 0, one byte of data to configure the internal register
address pointer, one or more bytes of data, and a
STOP condition. Figure 9 illustrates the proper frame
format for writing one byte of data to the MAX9860.
Figure 10 illustrates the frame format for writing n bytes
of data to the MAX9860.
The slave address with the R/Wbit set to 0 indicates
that the master intends to write data to the MAX9860.
The MAX9860 acknowledges receipt of the address
byte during the master-generated 9th SCL pulse.
The second byte transmitted from the master config-
ures the MAX9860’s internal register address pointer.
The pointer tells the MAX9860 where to write the next
byte of data. An acknowledge pulse is sent by the
MAX9860 upon receipt of the address pointer data.
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 33
SCL
SDA
tRtF
tBUF
START
CONDITION
STOP
CONDITION
REPEATED START CONDITION
START CONDITION
tSU,STO
tHD,STA
tSU,STA
tHD,DAT
tSU,DAT
tLOW
tHIGH
tHD,STA
tSP
Figure 6. 2-Wire Interface Timing Diagram
MAX9860
The third byte sent to the MAX9860 contains the data
that is written to the chosen register. An acknowledge
pulse from the MAX9860 signals receipt of the data byte.
The address pointer autoincrements to the next register
address after each received data byte. This autoincre-
ment feature allows a master to write to sequential regis-
ters within one continuous frame. Figure 10 illustrates
how to write to multiple registers with one frame. The
master signals the end of transmission by issuing a
STOP condition. Register addresses greater than 0x10
are reserved. Do not write to these addresses.
Read Data Format
Send the slave address with the R/Wbit set to 1 to initi-
ate a read operation. The MAX9860 acknowledges
receipt of its slave address by pulling SDA low during
the 9th SCL clock pulse. A START command followed
by a read command resets the address pointer to reg-
ister 0x00.
The first byte transmitted from the MAX9860 is the con-
tents of register 0x00. Transmitted data is valid on the
rising edge of SCL. The address pointer autoincre-
ments after each read data byte. This autoincrement
16-Bit Mono Audio Voice Codec
34 ______________________________________________________________________________________
SCL
SDA
SSrP
Figure 7. START (S), STOP (P), and REPEATED START (Sr) Conditions
1
SCL
START
CONDITION
SDA
28 9
CLOCK PULSE FOR
ACKNOWLEDGMENT
ACKNOWLEDGE
NOT ACKNOWLEDGE
Figure 8. Acknowledge
A
0SLAVE ADDRESS REGISTER ADDRESS DATA BYTE
ACKNOWLEDGE FROM MAX9860
R/W 1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
ACKNOWLEDGE FROM MAX9860
ACKNOWLEDGE FROM MAX9860
B1 B0B3 B2B5 B4B7 B6
S AA P
Figure 9. Writing One Byte of Data to the MAX9860
feature allows all registers to be read sequentially within
one continuous frame. A STOP (P) condition can be
issued after any number of read data bytes. If a STOP
condition is issued followed by another read operation,
the first data byte to be read is from register 0x00.
The address pointer can be preset to a specific register
before a read command is issued. The master presets
the address pointer by first sending the MAX9860’s
slave address with the R/Wbit set to 0 followed by the
register address. A REPEATED START (Sr) condition is
then sent followed by the slave address with the R/Wbit
set to 1. The MAX9860 then transmits the contents of
the specified register. The address pointer autoincre-
ments after transmitting the first byte.
The master acknowledges receipt of each read byte
during the acknowledge clock pulse. The master must
acknowledge all correctly received bytes except the
last byte. The final byte must be followed by a not
acknowledge from the master and then a STOP condi-
tion. Figure 11 illustrates the frame format for reading
one byte from the MAX9860. Figure 12 illustrates the
frame format for reading multiple bytes from the
MAX9860.
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 35
1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
ACKNOWLEDGE FROM MAX9860
ACKNOWLEDGE FROM MAX9860
B1 B0B3 B2B5 B4B7 B6
AA0
ACKNOWLEDGE FROM MAX9860
R/W
SA
1 BYTE
ACKNOWLEDGE FROM MAX9860
B1 B0B3 B2B5 B4B7 B6
P
A
SLAVE ADDRESS REGISTER ADDRESS DATA BYTE 1 DATA BYTE n
Figure 10. Writing N Bytes of Data to the MAX9860
ACKNOWLEDGE FROM MAX9860
1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
ACKNOWLEDGE FROM MAX9860
NOT ACKNOWLEDGE FROM MASTER
AA P
A
0
ACKNOWLEDGE FROM MAX9860
R/W
SA
R/WREPEATED START
Sr 1SLAVE ADDRESS REGISTER ADDRESS SLAVE ADDRESS DATA BYTE
Figure 11. Reading One Byte of Data from the MAX9860
ACKNOWLEDGE FROM MAX9860
1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
ACKNOWLEDGE FROM MAX9860
AA AP
0
ACKNOWLEDGE FROM MAX9860
R/W
SA
R/W
REPEATED START
Sr 1SLAVE ADDRESS REGISTER ADDRESS SLAVE ADDRESS DATA BYTE
Figure 12. Reading N Bytes of Data from the MAX9860
Applications Information
Proper layout and grounding are essential for optimum
performance. When designing a PCB for the MAX9860,
partition the circuitry so that the analog sections of the
MAX9860 are separated from the digital sections. This
ensures that the analog audio traces do not need to be
routed near digital traces.
Use a large continuous ground plane on a dedicated
layer of the PCB to minimize loop areas. Connect
AGND, DGND, and MICGND directly to the ground
plane using the shortest trace length possible. Proper
grounding improves audio performance, minimizes
crosstalk between channels, and prevents any digital
noise from coupling into the analog audio signal.
Ground the bypass capacitors on REG, PREG, and REF
directly to the ground plane with minimum trace length.
Also be sure to minimize the path length to AGND and
MICGND. Bypass AVDD directly to AGND. Bypass
MICBIAS directly to MICGND.
Connect all digital I/O termination to the ground plane
with minimum path length to DGND. Bypass DVDD and
DVDDIO directly to DGND.
Route microphone signals from the microphone to the
MAX9860 as a differential pair, ensuring that the positive
and negative signals follow the same path as closely as
possible with equal trace length. When using single-
ended microphones or other single-ended audio
sources, AC ground the negative microphone input sig-
nal as near to the audio source as possible and then treat
the positive and negative traces as differential pairs.
The MAX9860 thin QFN package features an exposed
thermal pad on its underside. This pad lowers the pack-
age’s thermal resistance by providing a direct heat
conduction path from the die to the PCB. Connect the
exposed thermal pad to AGND.
An evaluation kit (EV kit) is available to provide an
example layout for the MAX9860. The EV kit allows
quick setup of the MAX9860 and includes easy-to-use
software allowing all internal registers to be controlled.
MAX9860
16-Bit Mono Audio Voice Codec
36 ______________________________________________________________________________________
2324 22 21
879
REG
REF
AGND
AVDD
10
MICBIAS
LRCLK
SDOUT
MCLK
BCLK
DVDD
1
2
MICLN
4
5
6
17
18
16
14
13
MICLP
MICGND
SCL
SDA
OUTN
OUTP
MAX9860
PREG SDIN
3
15
MICRP
20
11
DVDDIO MICRN
19
12
DGND IRQ
THIN QFN
4mm x 4mm
TOP VIEW
*EP
*EP = EXPOSED PAD
+
Pin Configuration
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 37
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
PP
P
0 TO +20dB
(1dB STEPS)
DAC
DVDDIO
IRQ
14
MCLK
10
SCL
9
SDA
AGND
5
I2C SERIAL
PORT
23
22
0,
20dB,
30dB
21
20
0,
20dB,
30dB
LEFT
ADC
RIGHT
ADC
INTERPOLATION
FILTER
DECIMATION
FILTER
INTERNAL REGULATORS
REG
2
PREG
3
REF
4
DIGITAL AUDIO
INTERFACE
17
LRCLK
18
BCLK
16
SDIN
15
SDOUT
MONO
LOW-LEVEL
AUDIO
QUIETING
CONTROL
AUTOMATIC
GAIN
CONTROL
TIMING AND
CONTROL LOGIC
6
AVDD
1.7V TO 1.9V 1.7V TO 1.9V
STATUS
USER-
PROGRAMMABLE
MODE CONTROL
DGND
12
DIGITAL ANALOG
MICLP
MICLN
MICRP
MICRN
0 TO +20dB
(1dB STEPS)
MICBIAS
MICBIAS
1
24
MICGND
7
8
OUTP
OUTN
INDICATES USER PROGRAMMABLE I2C CONTROL BITS.
0, +6dB,
+12dB, +24dB -90dB TO 0
-60dB TO 0dB
(2dB STEPS)
-12dB TO +3dB
11
DVDDIO DVDD
13
1.7V TO 3.6V
DVDDIO
19
DVG DVA
DVST
PAM
PGAM
PAM
PGAM
ADCLL/
ADCRL
10kΩ
1.5kΩ1.5kΩ
10µF
0.1µF
1µF
1µF
1µF
1µF
1µF
2.2µF
1µF1µF2.2µF
1µF
P
MAX9860
Σ
Functional Diagram/Typical Operating Circuit
MAX9860
16-Bit Mono Audio Voice Codec
38 ______________________________________________________________________________________
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
24L QFN THIN.EPS
PACKAGE TYPE PACKAGE CODE DOCUMENT NO.
24 TQFN-EP T2444+4 21-0139
MAX9860
16-Bit Mono Audio Voice Codec
______________________________________________________________________________________ 39
Package Information (continued)
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
MAX9860
16-Bit Mono Audio Voice Codec
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
40
____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
Revision History
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
0 10/08 Initial release —
1 9/09 Corrected error in Table 11 32