RX
TX
POWER
APD
EN [RX]
DIN
ROUT
DOUT
RS232
RIN
RS232
1 1
1 1
FORCEON
FORCEOFF
STATUS
INVALID
3.3 V, 5 V
Product
Folder
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Technical
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Design
MAX3221
SLLS348O –JUNE 1999–REVISED JUNE 2015
MAX3221 3-V to 5.5-V RS-232 Line Driver and Receiver
With ±15-kV ESD Protection
1 Features 3 Description
The MAX3221 device consists of one line driver, one
1• RS-232 Bus-Pin ESD Protection Exceeds line receiver with dedicated enable pin, and a dual
±15 kV Using Human Body Model (HBM) charge-pump circuit with ±15-kV ESD protection pin
• Meets or Exceeds the Requirements of to pin (serial-port connection pins, including GND).
TIA/EIA-232-F and ITU V.28 Standards The device meets the requirements of TIA/EIA-232-F
and provides the electrical interface between an
• Operates With 3-V to 5.5-V VCC Supply asynchronous communication controller and the
• Operates up to 250 kbps serial-port connector. The charge pump and four
• One Driver and One Receiver small external capacitors allow operation from a
• Low Standby Current: 1 μA Typical single 3-V to 5.5-V supply. These devices operate at
data signaling rates up to 250 kbps and a maximum
• External Capacitors: 4 × 0.1 μFof 30-V/μs driver output slew rate.
• Accepts 5-V Logic Input With 3.3-V Supply Flexible control options for power management are
• Alternative High-Speed Pin-Compatible available when the serial port is inactive. The
Device (1 Mbps) automatic power-down feature functions when
– SNx5C3221 FORCEON is low and FORCEOFF is high. During
• Automatic Power-Down Feature Automatically this mode of operation, if the device does not sense a
valid
Disables Drivers for Power Savings RS-232 signal on the receiver input, the driver output
is disabled and the supply current is reduced to 1 μA.
2 Applications The INVALID output notifies the user if an RS-232
• Battery-Powered, Hand-Held, and Portable signal is present at the receiver input.
Equipment Device Information(1)
• Notebooks, Subnotebooks, and Laptops PART NUMBER PACKAGE BODY SIZE (NOM)
• Digital Cameras MAX3221xDB SSOP (32) 6.20 mm × 5.30 mm
• Mobile Phones and Wireless Devices MAX3221xPW TSSOP (32) 5.00 mm × 4.40 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Simplified Diagram
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
MAX3221
SLLS348O –JUNE 1999–REVISED JUNE 2015
www.ti.com
Table of Contents
1 Features.................................................................. 18 Detailed Description............................................ 11
8.1 Overview................................................................. 11
2 Applications ........................................................... 18.2 Functional Block Diagram....................................... 11
3 Description............................................................. 18.3 Feature Description................................................. 11
4 Revision History..................................................... 28.4 Device Functional Modes........................................ 12
5 Pin Configuration and Functions......................... 39 Application and Implementation ........................ 13
6 Specifications......................................................... 49.1 Application Information............................................ 13
6.1 Absolute Maximum Ratings ...................................... 49.2 Typical Application.................................................. 13
6.2 ESD Ratings.............................................................. 410 Power Supply Recommendations ..................... 14
6.3 Recommended Operating Conditions....................... 411 Layout................................................................... 15
6.4 Thermal Information.................................................. 511.1 Layout Guidelines ................................................. 15
6.5 Electrical Characteristics – Power ............................ 511.2 Layout Example .................................................... 15
6.6 Electrical Characteristics – Driver............................. 512 Device and Documentation Support................. 16
6.7 Electrical Characteristics – Receiver ........................ 612.1 Community Resources.......................................... 16
6.8 Electrical Characteristics – Status ........................... 612.2 Trademarks........................................................... 16
6.9 Switching Characteristics – Driver............................ 612.3 Electrostatic Discharge Caution............................ 16
6.10 Switching Characteristics – Receiver ..................... 712.4 Glossary................................................................ 16
6.11 Switching Characteristics – Status.......................... 7
6.12 Typical Characteristics............................................ 713 Mechanical, Packaging, and Orderable
Information........................................................... 16
7 Parameter Measurement Information .................. 8
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision N (January 2014) to Revision O Page
• Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional
Modes,Application and Implementation section, Power Supply Recommendations section, Layout section, Device
and Documentation Support section, and Mechanical, Packaging, and Orderable Information section .............................. 1
Changes from Revision M (March 2004) to Revision N Page
• Updated document to new TI data sheet format - no specification changes......................................................................... 1
• Deleted Ordering Information table. ....................................................................................................................................... 1
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1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
EN
C1+
V+
C1−
C2+
C2−
V−
RIN
FORCEOFF
VCC
GND
DOUT
FORCEON
DIN
INVALID
ROUT
MAX3221
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SLLS348O –JUNE 1999–REVISED JUNE 2015
5 Pin Configuration and Functions
DB or PW Package
16-Pin SSOP or TSSOP
Top View
Pin Functions
PIN I/O DESCRIPTION
NAME NO.
C1+ 2 — Positive terminals of the voltage-doubler charge-pump capacitors
C2+ 5
C1– 4 — Negative terminals of the voltage-doubler charge-pump capacitors
C2– 6
DIN 11 I Driver input
DOUT 13 O RS-232 driver output
EN 1 I Low input enables receiver ROUT output. High input sets ROUT to high impedance.
FORCEOFF 16 I Automatic power-down control input
FORCEON 12 I Automatic power-down control input
GND 14 — Ground
INVALID 10 O Invalid output pin. Output low when all RIN inputs are unpowered.
RIN 8 I RS-232 receiver input
ROUT 9 O Receiver output
VCC 15 — 3-V to 5.5-V supply voltage
V+ 3 O 5.5-V supply generated by the charge pump
V– 7 O –5.5-V supply generated by the charge pump
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6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
VCC to GND –0.3 6
V+ to GND –0.3 7 V
V– to GND 0.3 –7
V+ + |V–|(2) 13
DIN, EN, FORCEOFF , and FORCEON to GND –0.3 6
VIInput voltage V
RIN to GND ±25
DOUT to GND ±13.2
VOOutput voltage V
ROUT to GND –0.3 VCC + 0.3
TJJunction temperature(3) 150 °C
Tstg Storage temperature range –65 150
(1) 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 under Recommended Operating
Conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) V+ and V– can have maximum magnitudes of 7 V, but their absolute difference cannot exceed 13 V.
(3) Maximum power dissipation is a function of TJ(max), RθJA, and TA. The maximum allowable power dissipation at any allowable ambient
temperature is PD= (TJ(max) – TA) / RθJA. Operating at the absolute maximum TJof 150°C can affect reliability.
6.2 ESD Ratings VALUE UNIT
All pins except 8, 13 ±3000
Human body model (HBM), per
ANSI/ESDA/JEDEC JS-001(1) Pins 8, 13 ±15,000
V(ESD) Electrostatic discharge V
Charged-device model (CDM), per JEDEC specification JESD22- ±1500
C101(2)
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
(see Figure 8)(1)
MIN NOM MAX UNIT
VCC = 3.3 V 3 3.3 3.6
Supply voltage V
VCC = 5 V 4.5 5 5.5
VCC = 3.3 V 2
DIN, FORCEOFF,
VIH Driver high-level input voltage V
FORCEON, EN VCC = 5 V 2.4
DIN, FORCEOFF,
VIL Driver low-level input voltage 0.8 V
FORCEON, EN
DIN, FORCEOFF,
Driver input voltage 0 5.5
FORCEON, EN
VIV
Receiver input voltage –25 25
MAX3221C 0 70
TAOperating free-air temperature °C
MAX3221I –40 85
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
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6.4 Thermal Information MAX3221
THERMAL METRIC(1) DB (SSOP) PW (TSSOP) UNIT
16 PINS 16 PINS
RθJA Junction-to-ambient thermal resistance 98.0 106.4 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 48.3 41.1 °C/W
RθJB Junction-to-board thermal resistance 48.7 51.4 °C/W
ψJT Junction-to-top characterization parameter 10.1 3.9 °C/W
ψJB Junction-to-board characterization parameter 48.1 50.9 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report, SPRA953.
6.5 Electrical Characteristics – Power
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(1)
PARAMETER TEST CONDITIONS MIN TYP(2) MAX UNIT
Input leakage
IIFORCEOFF, FORCEON, EN ±0.01 ±1 µA
current
Automatic power-down No load, FORCEOFF and 0.3 1 mA
disabled FORCEON at VCC
Powered off No load, No load, FORCEOFF at GND 1 10
ICC Supply current VCC = 3.3 V to 5 V No load, FORCEOFF at VCC,µA
Automatic power-down enabled FORCEON at GND, 1 10
All RIN are open or grounded
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
(2) All typical values are at VCC = 3.3 V or VCC = 5 V, and TA= 25°C.
6.6 Electrical Characteristics – Driver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(1)
PARAMETER TEST CONDITIONS MIN TYP(2) MAX UNIT
VOH High-level output voltage DOUT at RL= 3 kΩto GND, DIN = GND 5 5.4 V
VOL Low-level output voltage DOUT at RL= 3 kΩto GND, DIN = VCC –5 –5.4 V
IIH High-level input current VI= VCC ±0.01 ±1 μA
IIL Low-level input current VIat GND ±0.01 ±1 μA
VCC = 3.6 V VO= 0 V ±35 ±60
IOS Short-circuit output current(3) mA
VCC = 5.5 V VO= 0 V ±35 ±60
rOOutput resistance VCC, V+, and V– = 0 V VO= ±2 V 300 10M Ω
VO= ±12 V, ±25
VCC = 3 V to 3.6 V
Ioff Output leakage current FORCEOFF = GND µA
VO= ±12 V, ±25
VCC = 4.5 V to 5.5 V
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5
(2) All typical values are at VCC = 3.3 V or VCC = 5 V, and TA= 25°C.
(3) Short-circuit durations should be controlled to prevent exceeding the device absolute power dissipation ratings, and not more than one
output should be shorted at a time.
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6.7 Electrical Characteristics – Receiver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(1)
PARAMETER TEST CONDITIONS MIN TYP(2) MAX UNIT
VOH High-level output voltage IOH = –1 mA VCC – 0.6 VCC – 0.1 V
VOL Low-level output voltage IOL = 1.6 mA 0.4 V
VCC = 3.3 V 1.5 2.4
VIT+ Positive-going input threshold voltage V
VCC = 5 V 1.8 2.4
VCC = 3.3 V 0.6 1.1
VIT– Negative-going input threshold voltage V
VCC = 5 V 0.8 1.4
Vhys Input hysteresis (VIT+ – VIT–) 0.5 V
Ioff Output leakage current FORCEOFF = 0 V ±0.05 ±10 µA
riInput resistance VI= ±3 V to ±25 V 3 5 7 kΩ
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
(2) All typical values are at VCC = 3.3 V or VCC = 5 V, and TA= 25°C.
6.8 Electrical Characteristics – Status
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(1)
PARAMETER TEST CONDITIONS MIN TYP(2) MAX UNIT
Receiver input threshold for INVALID FORCEON = GND,
VT+(valid) 2.7 V
high-level output voltage FORCEOFF = VCC
Receiver input threshold for INVALID FORCEON = GND,
VT–(valid) –2.7 V
high-level output voltage FORCEOFF = VCC
Receiver input threshold for INVALID low- FORCEON = GND,
VT(invalid) –0.3 0.3 V
level output voltage FORCEOFF = VCC
IOH = –1 mA,
VOH INVALID high-level output voltage FORCEON = GND, VCC – 0.6 V
FORCEOFF = VCC
IOH = –1 mA,
VOL INVALID low-level output voltage FORCEON = GND, 0.4 V
FORCEOFF = VCC
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
(2) All typical values are at VCC = 3.3 V or VCC = 5 V, and TA= 25°C.
6.9 Switching Characteristics – Driver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(1)
PARAMETER TEST CONDITIONS MIN TYP(2) MAX UNIT
CL= 1000 pF, RL= 3 kΩ,
Maximum data rate 150 250 kbps
see Figure 3
CL= 150 to 2500 pF, RL= 3 kΩto 7 kΩ,
tsk(p) Pulse skew(3) 100 ns
see Figure 4 CL= 150 to 1000 pF 6 30
Slew rate, transition region VCC = 3.3 V,
SR(tr) V/μs
(see Figure 3) RL= 3 kΩto 7 kΩCL= 150 to 2500 pF 4 30
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
(2) All typical values are at VCC = 3.3 V or VCC = 5 V, and TA= 25°C.
(3) Pulse skew is defined as |tPLH −tPHL| of each channel of the same device.
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0
1
2
3
4
5
6
0 5 10 15 20 25
DOUT Voltage (V)
DOUT Current (mA)
VOH
C001
±6
±5
±4
±3
±2
±1
0
0 5 10 15 20 25
DOUT Voltage (V)
DOUT Current (mA)
VOL
C001
MAX3221
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6.10 Switching Characteristics – Receiver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(1)
PARAMETER TEST CONDITIONS MIN TYP(2) MAX UNIT
CL= 150 pF,
tPLH Propagation delay time, low- to high-level output 150 ns
see Figure 5
CL= 150 pF,
tPHL Propagation delay time, high- to low-level output 150 ns
see Figure 5
CL= 150 pF, RL= 3 kΩ,
ten Output enable time 200 ns
see Figure 6
CL= 150 pF, RL= 3 kΩ,
tdis Output disable time 200 ns
see Figure 6
tsk(p) Pulse skew(3) See Figure 5 50 ns
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
(2) All typical values are at VCC = 3.3 V or VCC = 5 V, and TA= 25°C.
(3) Pulse skew is defined as |tPLH −tPHL| of each channel of the same device.
6.11 Switching Characteristics – Status
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(1)
PARAMETER MIN TYP(2) MAX UNIT
tvalid Propagation delay time, low- to high-level output 1 µs
tinvalid Propagation delay time, high- to low-level output 30 µs
ten Supply enable time 100 µs
(1) Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
(2) All typical values are at VCC = 3.3 V or VCC = 5 V, and TA= 25°C.
6.12 Typical Characteristics
VCC = 3.3 V
Figure 1. DOUT VOH vs Load Current Figure 2. DOUT VOL vs Load Current
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50 Ω
TEST CIRCUIT VOLTAGE WAVEFORMS
0 V
3 V
Output
Input
VOL
VOH
tPLH
Generator
(see Note B) RL
3 V
FORCEOFF
RS-232
Output
tPHL
CL
(see Note A)
50% 50%
1.5 V 1.5 V
50 Ω
TEST CIRCUIT VOLTAGE WAVEFORMS
−3 V
−3 V
3 V
3 V
0 V
3 V
Output
Input
VOL
VOH
tTLH
Generator
(see Note B) RL
3 V
FORCEOFF
RS-232
Output
tTHL
CL
(see Note A)
SR(tr) = 6 V
tTHL or tTLH
MAX3221
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7 Parameter Measurement Information
A. CLincludes probe and jig capacitance.
B. The pulse generator has the following characteristics: PRR = 250 kbps, ZO= 50 Ω, 50% duty cycle, tr≤10 ns,
tf≤10 ns.
Figure 3. Driver Slew Rate
A. CLincludes probe and jig capacitance.
B. The pulse generator has the following characteristics: PRR = 250 kbps, ZO= 50 Ω, 50% duty cycle, tr≤10 ns,
tf≤10 ns.
Figure 4. Driver Pulse Skew
A. CLincludes probe and jig capacitance.
B. The pulse generator has the following characteristics: ZO= 50 Ω, 50% duty cycle, tr≤10 ns, tf≤10 ns.
Figure 5. Receiver Propagation Delay Times
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TEST CIRCUIT VOLTAGE WAVEFORMS
50 Ω
Generator
(see Note B)
3 V or 0 V
Output
VOL
VOH
tPZH
(S1 at GND)
3 V
0 V
0.3 V
Output
Input
0.3 V
3 V or 0 V
FORCEON
EN
1.5 V 1.5 V
50%
tPHZ
(S1 at GND)
tPLZ
(S1 at VCC)
50%
tPZL
(S1 at VCC)
RL
S1
VCC GND
CL
(see Note A)
Output
MAX3221
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Parameter Measurement Information (continued)
A. CLincludes probe and jig capacitance.
B. The pulse generator has the following characteristics: ZO= 50 Ω, 50% duty cycle, tr≤10 ns, tf≤10 ns.
C. tPLZ and tPHZ are the same as tdis.
D. tPZL and tPZH are the same as ten.
Figure 6. Receiver Enable and Disable Times
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TEST CIRCUIT
50 Ω
Generator
(see Note B)
FORCEOFF
ROUT
FORCEON
Auto-
powerdown INVALID
DOUTDIN
CL= 30 pF
(see Note A)
2.7 V
−2.7 V
0.3 V
−0.3 V
0 V
Valid RS-232 Level, INVALID High
Indeterminate
Indeterminate
If Signal Remains Within This Region
For More Than 30 µs, INVALID Is Low†
Valid RS-232 Level, INVALID High
†Auto-powerdown disables drivers and reduces supply
current to 1 µA.
VOLTAGE WAVEFORMS
3 V
2.7 V
−2.7 V
INVALID
Output
Receiver
Input
tvalid
0 V
0 V
−3 V
VCC
0 V
≈V+
0 V
≈V−
V+
VCC
ten
V−
50% VCC 50% VCC
2.7 V
−2.7 V
0.3 V
0.3 V
tinvalid
Supply
Voltages
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Parameter Measurement Information (continued)
Figure 7. INVALID Propagation Delay Times and Driver Enabling Time
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RX
TX
POWER
APD
EN [RX]
DIN
ROUT
DOUT
RS232
RIN
RS232
1 1
1 1
FORCEON
FORCEOFF
STATUS
INVALID
3.3V, 5V
MAX3221
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8 Detailed Description
8.1 Overview
The MAX3221 device is a one-driver and one-receiver RS-232 interface device. All RS-232 inputs and outputs
are protected to ±15 kV using the Human Body Model. The charge pump requires only four small 0.1-μF
capacitors for operation from a 3.3-V supply. The MAX3221 is capable of running at data rates up to 250 kbps,
while maintaining RS-232-compliant output levels.
Automatic power-down can be disabled when FORCEON and FORCEOFF are high. With automatic power-down
plus enabled, the device activates automatically when a valid signal is applied to any receiver input. The device
can automatically power down the driver to save power when the RIN input is unpowered.
INVALID is high (valid data) if receiver input voltage is greater than 2.7 V or less than –2.7 V, or has been
between –0.3 V and 0.3 V for less than 30 μs. INVALID is low (invalid data) if receiver input voltages are
between –0.3 V and 0.3 V for more than 30 μs. Refer to Figure 7 for receiver input levels.
8.2 Functional Block Diagram
8.3 Feature Description
8.3.1 Power
The power block increases, inverts, and regulates voltage at V+ and V- pins using a charge pump that requires
four external capacitors. Auto-power-down feature for driver is controlled by FORCEON and FORCEOFF inputs.
Receiver is controlled by EN input. See Table 1 and Table 2
When MAX3221 is unpowered, it can be safely connected to an active remote RS232 device.
8.3.2 RS232 Driver
One driver interfaces standard logic level to RS232 levels. DIN input must be valid high or low.
8.3.3 RS232 Receiver
One receiver interfaces RS232 levels to standard logic levels. An open input will result in a high output on ROUT.
RIN input includes an internal standard RS232 load. A logic high input on the EN pin will shutdown the receiver
output.
8.3.4 RS232 Status
The INVALID output goes low when RIN input is unpowered for more than 30 μs. The INVALID output goes high
when receiver has a valid input. The INVALID output is active when Vcc is powered irregardless of FORCEON
and FORCEOFF inputs (see Table 3).
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DIN DOUT
Auto-powerdown INVALID
RIN
FORCEOFF
FORCEON
ROUT
EN
11
16
9
13
10
8
1
12
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8.4 Device Functional Modes
Table 1,Table 2, and Table 3 show the behavior of the driver, receiver, and INVALID(activelow) features under
all possible relevant combinations of inputs.
Table 1. Driver(1)
INPUTS OUTPUT DRIVER STATUS
VALID RIN RS-232
DIN FORCEON FORCEOFF DOUT
LEVEL
X X L X Z Powered off
L H H X H Normal operation with
automatic power down disabled
H H H X L
L L H Yes H Normal operation with
automatic power down enabled
H L H Yes L
L L H No Z Powered off by
automatic power down feature
H L H No Z
(1) H = high level, L = low level, X = irrelevant, Z = high impedance, Yes = |RIN| > 2.7 V, No = |RIN| <0.3 V
Table 2. Receiver(1)
INPUTS OUTPUT RECEIVER STATUS
VALID RIN RS-232
RIN EN ROUT
LEVEL
X H X Z Output off
L L X H
H L X L Normal operation
Open L No H
(1) H = high level, L = low level, X = irrelevant, Z = high impedance (off), Open = input disconnected or connected driver off
Table 3. INVALID(1)
INPUTS OUTPUT
RIN FORCEON FORCEOFF EN INVALID
L X X X H
H X X X H
Open X X X L
(1) H = high level, L = low level, X = irrelevant, Z = high impedance (off), Open = input disconnected or connected driver off
Logic Diagram
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CBYPASS = 0.1 µF
Auto-
powerdown
VCC C1 C2, C3, and C4
3.3 V ±0.3 V
5 V ±0.5 V
3 V to 5.5 V
0.1 µF
0.047 µF
0.1 µF
0.1 µF
0.33 µF
0.47 µF
VCC vs CAPACITOR VALUES
FORCEOFF
+
−
+
−
+
−
+
−
+
−
1
8
2
3
5
6
7
4
16
13
12
11
10
9
15
14
VCC
GND
C1+
V+
C2+
C1−
C2−
V−
DOUT
FORCEON
DIN
INVALID
ROUT
EN
RIN
C1
C2
C4
5 kΩ
C3†
†C3 can be connected to VCC or GND.
NOTES: A. Resistor values shown are nominal.
B. Nonpolarized ceramic capacitors are acceptable. If polarized tantalum or electrolytic capacitors are used, they should be
connected as shown.
MAX3221
www.ti.com
SLLS348O –JUNE 1999–REVISED JUNE 2015
9 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
9.1 Application Information
The MAX3221 line driver and receiver is a specialized device for 3-V to 5.5-V RS-232 communication
applications. This application is a generic implementation of this device with all required external components.
For proper operation, add capacitors as shown in Figure 8.
9.2 Typical Application
ROUT and DIN connect to UART or general purpose logic lines. FORCEON and FORCEOFF may be connected
general purpose logic lines or tied to ground or VCC. INVALID may be connected to a general purpose logic line
or left unconnected. RIN and DOUT lines connect to a RS232 connector or cable. DIN, FORCEON, and
FORCEOFF inputs must not be left unconnected.
Figure 8. Typical Operating Circuit and Capacitor Values
Copyright © 1999–2015, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: MAX3221
±6
±5
±4
±3
±2
±1
0
1
2
3
4
5
6
0 1 2 3 4 5 6 7 8 9 10
Voltage (V)
Time (s)
DIN
DOUT to RIN
ROUT
C001
MAX3221
SLLS348O –JUNE 1999–REVISED JUNE 2015
www.ti.com
Typical Application (continued)
9.2.1 Design Requirements
• Recommended VCC is 3.3 V or 5 V.
– 3 V to 5.5 V is also possible
• Maximum recommended bit rate is 250 kbps.
• Use capacitors as shown in Figure 8.
9.2.2 Detailed Design Procedure
• DIN, FORCEOFF and FORCEON inputs must be connected to valid low or high logic levels.
• Select capacitor values based on VCC level for best performance.
9.2.3 Application Curve
Curves for VCC of 3.3 V and 250 kbps alternative bit data stream.
Figure 9. 250-kbps Driver to Receiver Loopback Timing Waveform,
VCC= 3.3 V
10 Power Supply Recommendations
TI recommends a 0.1-μF capacitor to filter noise on the power supply pin. For additional filter capability, a
0.01-μF capacitor may be added in parallel as well. Power supply input voltage is recommended to be any valid
level in Recommended Operating Conditions.
14 Submit Documentation Feedback Copyright © 1999–2015, Texas Instruments Incorporated
Product Folder Links: MAX3221
VCC
Ground
Ground
14
13
15
12
11
10
9
1
2
3
4
5
6
7
8
16
C2
C1
Ground
C3
C4
PF
C1+
V+
C1-
C2+
C2-
V-
RIN
VCC
GND
DOUT
FORCEON
DIN
INVALID
ROUT
EN FORCEOFF
MAX3221
www.ti.com
SLLS348O –JUNE 1999–REVISED JUNE 2015
11 Layout
11.1 Layout Guidelines
Keep the external capacitor traces short. This is more important on C1 and C2 nodes that have the fastest rise
and fall times.
11.2 Layout Example
Figure 10. Layout Diagram
Copyright © 1999–2015, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: MAX3221
MAX3221
SLLS348O –JUNE 1999–REVISED JUNE 2015
www.ti.com
12 Device and Documentation Support
12.1 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
12.2 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
12.3 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
12.4 Glossary
SLYZ022 —TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
13 Mechanical, Packaging, and Orderable Information
The following pages include mechanical packaging and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser based versions of this data sheet, refer to the left hand navigation.
16 Submit Documentation Feedback Copyright © 1999–2015, Texas Instruments Incorporated
Product Folder Links: MAX3221
PACKAGE OPTION ADDENDUM
www.ti.com 24-Aug-2018
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
MAX3221CDB ACTIVE SSOP DB 16 80 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CDBE4 ACTIVE SSOP DB 16 80 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CDBR ACTIVE SSOP DB 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CDBRG4 ACTIVE SSOP DB 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CPW ACTIVE TSSOP PW 16 90 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CPWE4 ACTIVE TSSOP PW 16 90 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CPWR ACTIVE TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CPWRE4 ACTIVE TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221CPWRG4 ACTIVE TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM 0 to 70 MA3221C
MAX3221IDB ACTIVE SSOP DB 16 80 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IDBE4 ACTIVE SSOP DB 16 80 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IDBG4 ACTIVE SSOP DB 16 80 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IDBR ACTIVE SSOP DB 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IDBRE4 ACTIVE SSOP DB 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IDBRG4 ACTIVE SSOP DB 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IPW ACTIVE TSSOP PW 16 90 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IPWG4 ACTIVE TSSOP PW 16 90 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
PACKAGE OPTION ADDENDUM
www.ti.com 24-Aug-2018
Addendum-Page 2
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
MAX3221IPWR ACTIVE TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU | CU SN Level-1-260C-UNLIM -40 to 85 MB3221I
MAX3221IPWRG4 ACTIVE TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 85 MB3221I
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
OTHER QUALIFIED VERSIONS OF MAX3221 :
PACKAGE OPTION ADDENDUM
www.ti.com 24-Aug-2018
Addendum-Page 3
•Enhanced Product: MAX3221-EP
NOTE: Qualified Version Definitions:
•Enhanced Product - Supports Defense, Aerospace and Medical Applications
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
MAX3221CDBR SSOP DB 16 2000 330.0 16.4 8.2 6.6 2.5 12.0 16.0 Q1
MAX3221CPWR TSSOP PW 16 2000 330.0 12.4 6.9 5.6 1.6 8.0 12.0 Q1
MAX3221IDBR SSOP DB 16 2000 330.0 16.4 8.2 6.6 2.5 12.0 16.0 Q1
MAX3221IPWR TSSOP PW 16 2000 330.0 12.4 6.9 5.6 1.6 8.0 12.0 Q1
MAX3221IPWR TSSOP PW 16 2000 330.0 12.4 6.9 5.6 1.6 8.0 12.0 Q1
MAX3221IPWRG4 TSSOP PW 16 2000 330.0 12.4 6.9 5.6 1.6 8.0 12.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 29-Apr-2014
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
MAX3221CDBR SSOP DB 16 2000 367.0 367.0 38.0
MAX3221CPWR TSSOP PW 16 2000 367.0 367.0 35.0
MAX3221IDBR SSOP DB 16 2000 367.0 367.0 38.0
MAX3221IPWR TSSOP PW 16 2000 364.0 364.0 27.0
MAX3221IPWR TSSOP PW 16 2000 367.0 367.0 35.0
MAX3221IPWRG4 TSSOP PW 16 2000 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 29-Apr-2014
Pack Materials-Page 2
MECHANICAL DATA
MSSO002E – JANUARY 1995 – REVISED DECEMBER 2001
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
DB (R-PDSO-G**) PLASTIC SMALL-OUTLINE
4040065 /E 12/01
28 PINS SHOWN
Gage Plane
8,20
7,40
0,55
0,95
0,25
38
12,90
12,30
28
10,50
24
8,50
Seating Plane
9,907,90
30
10,50
9,90
0,38
5,60
5,00
15
0,22
14
A
28
1
2016
6,50
6,50
14
0,05 MIN
5,905,90
DIM
A MAX
A MIN
PINS **
2,00 MAX
6,90
7,50
0,65 M
0,15
0°–ā8°
0,10
0,09
0,25
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion not to exceed 0,15.
D. Falls within JEDEC MO-150
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Copyright © 2018, Texas Instruments Incorporated
Mouser Electronics
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MAX3221CDBR MAX3221IPWR MAX3221CPWR MAX3221CDB MAX3221CDBE4 MAX3221CDBRG4
MAX3221CPW MAX3221CPWE4 MAX3221CPWG4 MAX3221CPWRE4 MAX3221CPWRG4 MAX3221IDB
MAX3221IDBE4 MAX3221IDBG4 MAX3221IDBRE4 MAX3221IDBRG4 MAX3221IPW MAX3221IPWE4
MAX3221IPWG4 MAX3221IPWRE4 MAX3221IPWRG4 MAX3221IDBR MAX3221CDBG4