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   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
1
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DQualified for Automotive Applications
DComplete PWM Power Control Circuitry
DCompletely Synchronized Operation
DInternal Undervoltage Lockout Protection
DWide Supply Voltage Range
DInternal Short-Circuit Protection
DOscillator Frequency ...500 kHz Max
DVariable Dead Time Provides Control Over
Total Range
DInternal Regulator Provides a Stable 2.5-V
Reference Supply
DAvailable in Q-Temp Automotive
HighRel Automotive Applications
Configuration Control / Print Support
Qualification to Automotive Standards
description
The TL1451A incorporates on a single monolithic chip all the functions required in the construction of two
pulse-width-modulation (PWM) control circuits. Designed primarily for power-supply control, the TL1451A
contains an on-chip 2.5-V regulator, two error amplifiers, an adjustable oscillator, two dead-time comparators,
undervoltage lockout circuitry, and dual common-emitter output transistor circuits.
The uncommitted output transistors provide common-emitter output capability for each controller. The internal
amplifiers exhibit a common-mode voltage range from 1.04 V to 1.45 V. The dead-time control (DTC)
comparator has no offset unless externally altered and can provide 0% to 100% dead time. The on-chip
oscillator can be operated by terminating RT and CT. During low VCC conditions, the undervoltage lockout
control circuit feature locks the outputs off until the internal circuitry is operational.
The TL1451A is characterized for operation from −40°C to 125°C.
AVAILABLE OPTIONS{
PACKAGED DEVICES}
TATSSOP
(PW)§
−40°C to 125°C TL1451AQPWRQ1
†For the most current package and ordering information, see the
Package Option Addendum at the end of this document, or see the TI
web site at http://www.ti.com.
‡Package drawings, thermal data, and symbolization are available at
http://www.ti.com/packaging.
§The PW package is only available left-end taped and reeled.
Copyright 2008, Texas Instruments Incorporated
   ! "#$ !  %#&'" ($)
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$!.  '' %$$!)
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
CT
RT
ERROR 1IN+
AMPLIFIER 1 1IN−
1FEEDBACK
1DTC
1OUT
GND
REF
SCP
2IN+ ERROR
2IN− AMPLIFIER 2
2FEEDBACK
2DTC
2OUT
VCC
PW PACKAGE
(TOP VIEW)
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
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SGLS304A − JUNE 2005 − REVISED JUNE 2008
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functional block diagram
+
−
+
−
Oscillator
Reference
Voltage
1/2 Vref
R
S
170 kΩUVLO
R
92 1
V
CC
RT CT
10
16
7
8
REF
GND
PWM
COMP
PWM
COMP
12 kΩ
11
14
13
12
5
15
3
4
6
2 DTC
IN+
IN−
2 FEEDBACK
1 FEEDBACK
SCP
IN+
IN−
1 DTC
ERROR
AMPLIFIER 2
ERROR
A
MPLIFIER 1 1 OUTPUT
2 OUTPUT
COMPONENT COUNT
Resistors 65
Capacitors 8
Transistors 105
JFETs 18
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SGLS304A − JUNE 2005 − REVISED JUNE 2008
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absolute maximum ratings over operating free-air temperature range†
Supply voltage, VCC 51 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Amplifier input voltage, VI20 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Collector output voltage, VO51 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Collector output current, IO21 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous power total dissipation See Dissipation Rating Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating free-air temperature range, TA−40°C to 125°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, Tstg −65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds 260°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
†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.
DISSIPATION RATING TABLE
PACKAGE TA ≤ 25°C
POWER RATING DERATING FACTOR
ABOVE TA = 25°CTA = 70°C
POWER RATING TA = 85°C
POWER RATING TA = 125°C
POWER RATING
PW 838 mW 6.7 mW/°C536 mW 436 mW 168 mW
recommended operating conditions
MIN MAX UNIT
Supply voltage, VCC 3.6 50 V
Amplifier input voltage, VI1.05 1.45 V
Collector output voltage, VO50 V
Collector output current, IO20 mA
Current into feedback terminal 45 µA
Feedback resistor, RF100 kΩ
Timing capacitor, CT150 15000 pF
Timing resistor, RT5.1 100 kΩ
Oscillator frequency 1 500 kHz
Operating free-air temperature, TA−40 125 °C
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SGLS304A − JUNE 2005 − REVISED JUNE 2008
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electrical characteristics over recommended operating free-air temperature range, VCC = 6 V,
f = 200 kHz (unless otherwise noted)
reference section
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
Output voltage (pin 16)
IO = 1 mA
TA = 25°C 2.4 2.5 2.6
V
Output voltage (pin 16) IO = 1 mA TA = MIN and 125°C 2.35 2.46 2.65 V
Output voltage change with temperature −0.63% ±4%}
TA = 25°C 2.0 12.5
Input voltage regulation V
CC
= 3.6 V to 40 V TA = 125°C 0.7 15 mV
Input voltage regulation
VCC = 3.6 V to 40 V
TA = MIN 0.3 30
mV
TA = 25°C 1 7.5
Output voltage regulation I
O
= 0.1 mA to 1 mA TA = 125°C 0.3 14 mV
Output voltage regulation
IO = 0.1 mA to 1 mA
TA = MIN 0.3 20
mV
Short-circuit output current VO = 0 3 10 30 mA
†All typical values are at TA = 25°C unless otherwise indicated.
‡These parameters are not production tested.
undervoltage lockout section
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
TA = 25°C 2.72
Upper threshold voltage (V
CC
)TA = 125°C 1.7 V
Upper threshold voltage (VCC)
TA = MIN 3.15
V
TA = 25°C 2.6
Lower threshold voltage (V
CC
)TA = 125°C 1.65 V
Lower threshold voltage (VCC)
TA = MIN 3.09
V
TA = 25°C 80 120
Hysteresis (V
CC
)TA = 125°C 10 50 mV
Hysteresis (VCC)
TA = MIN 10 60
mV
TA = 25°C 1.5
Reset threshold voltage (VCC)TA = 125°C 0.95 V
Reset threshold voltage (VCC)
TA = MIN 1.5
V
†All typical values are at TA = 25°C unless otherwise indicated.
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SGLS304A − JUNE 2005 − REVISED JUNE 2008
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short-circuit protection control section
TEST CONDITIONS
TL1451AQ
UNIT
TEST CONDITIONS
MIN TYP†MAX
UNIT
TA = 25°C 650 700 750
Input threshold voltage (SCP) TA = 125°C 400 478 650 mV
TA = MIN 800 880 950
mV
Standby voltage (SCP) 140 185 230 mV
TA = 25°C 60 120
Latched input voltage (SCP) TA = 125°C 70 120 mV
TA = MIN 60 120
mV
Equivalent timing resistance 170 kΩ
Comparator threshold voltage (FEEDBACK) 1.18 V
†All typical values are at TA = 25°C unless otherwise indicated.
oscillator section
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
CT = 330 pF,
TA = 25°C 200
Frequency CT = 330 pF,
RT = 10 kΩ
TA = 125°C 195 kHz
Frequency
RT = 10 kΩ
TA = MIN 193
kHz
Standard deviation of frequency CT = 330 pF, RT = 10 kΩ2%
TA = 25°C 1%
Frequency change with voltage V
CC
= 3.6 V to 40 V TA = 125°C 1%
Frequency change with voltage
VCC = 3.6 V to 40 V
TA = MIN 3%
Frequency change with temperature 1.37% ±10%}
†All typical values are at TA = 25°C unless otherwise indicated.
‡These parameters are not production tested.
dead-time control section
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
Input bias current (DTC)
TA = 25°C 1
A
Input bias current (DTC) TA = MIN and 125°C 3 µA
Latch mode (source) current (DTC) −80 −145 µA
TA = 25°C 2.3
Latched input voltage (DTC) TA = 125°C 2.22 2.32 V
Latched input voltage (DTC)
TA = MIN 2.28 2.4
V
Input threshold voltage at f = 10 kHz (DTC)
Zero duty cycle 2.05 2.25}
V
Input threshold voltage at f = 10 kHz (DTC)
Maximum duty cycle 1.2}1.45
V
†All typical values are at TA = 25°C unless otherwise indicated.
‡These parameters are not production tested.
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SGLS304A − JUNE 2005 − REVISED JUNE 2008
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error-amplifier section
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
TA = 25°C±7
Input offset voltage V
O
(FEEDBACK) = 1.25 V TA = 125°C±10 mV
Input offset voltage
VO (FEEDBACK) = 1.25 V
TA = MIN ±12
mV
TA = 25°C±100
Input offset current V
O
(FEEDBACK) = 1.25 V TA = 125°C±100 nA
Input offset current
VO (FEEDBACK) = 1.25 V
TA = MIN ±200
nA
TA = 25°C 160 500
Input bias current V
O
(FEEDBACK) = 1.25 V TA = 125°C 100 500 nA
Input bias current
VO (FEEDBACK) = 1.25 V
TA = MIN 142 700
nA
1.05
Common-mode input voltage range
VCC = 3.6 V to 40 V
1.05
to
V
Common-mode input voltage range
VCC = 3.6 V to 40 V
to
1.45
V
TA = 25°C 70 80
Open-loop voltage amplification R
F
= 200 kΩTA = 125°C 70 80 dB
Open-loop voltage amplification
RF = 200 kΩ
TA = MIN 64 80
dB
Unity-gain bandwidth 1.5 MHz
Common-mode rejection ratio 60 80 dB
Positive output voltage swing 2 V
Negative output voltage swing 1 V
TA = 25°C 0.5 1.6
Output (sink) current (FEEDBACK) V
ID
= −0.1 V, V
O
= 1.25 V TA = 125°C 0.4 1.8 mA
Output (sink) current (FEEDBACK)
VID = −0.1 V, VO = 1.25 V
TA = MIN 0.3 1.7
mA
TA = 25°C−45 −70
Output (source) current (FEEDBACK) V
ID
= 0.1 V, V
O
= 1.25 V TA = 125°C−25 −50 µA
Output (source) current (FEEDBACK)
VID = 0.1 V, VO = 1.25 V
TA = MIN −15 −70
µA
†All typical values are at TA = 25°C unless otherwise indicated.
output section
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
Collector off-state current VO = 50 V 10 µA
TA = 25°C 1.2 2
Output saturation voltage TA = 125°C 1.6 2.4 V
Output saturation voltage
TA = MIN 1.36 2.2
V
Short-circuit output current VO = 6 V 90 mA
†All typical values are at TA = 25°C unless otherwise indicated.
pwm comparator section
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
Input threshold voltage at f = 10 kHz (FEEDBACK)
Zero duty cycle 2.05 2.25}
V
Input threshold voltage at f = 10 kHz (FEEDBACK)
Maximum duty cycle 1.2}1.45
V
†All typical values are at TA = 25°C unless otherwise indicated.
‡These parameters are not production tested.
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total device
PARAMETER
TEST CONDITIONS
TL1451AQ
UNIT
PARAMETER
TEST CONDITIONS
MIN TYP†MAX
UNIT
Standby supply current Off-state 1.3 1.8 mA
Average supply current RT = 10 kΩ1.7 2.4 mA
†All typical values are at TA = 25°C unless otherwise indicated.
PARAMETER MEASUREMENT INFORMATION
87654321
910111213141516
S1
CPE 0.47 µF
Test
Input VCC = 5 V RL
4.7 kΩ
4.7 kΩ
RL
OUT1
OUT2
CT
330 pF RT
10 kΩ
Test
Input
TL1451A
Figure 1. Test Circuit
Dead Time 100%
tpe†
2.0 V
1.6 V
1.4 V
1.25 V
H
L
H
L
0.6 V
0 V
H
L
3.6 V
0 V
Oscillator Triangle W aveform
Error Amplifier Output
Dead-Time Input Voltage
Short-Circuit Protection
Comparator Input Voltage
PWM Comparator Output Voltage
Output Transistor Collector
Waveform
Protection Enable
Terminal W aveform
Short-Circuit Protection
Comparator Output
Power Supply Voltage
†Protection Enable Time, tpe = (0.051 x 106 x Cpe) in seconds
2.8 V TYP
Figure 2. TL1451A Timing Diagram
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SGLS304A − JUNE 2005 − REVISED JUNE 2008
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TYPICAL CHARACTERISTICS
100 k
10 k
1 k
1 M
1 k 4 k 10 k 40 k 100 k 400 k 1 M
TRIANGLE OSCILLATOR FREQUENCY
vs
TIMING RESISTANCE
CT = 150 pF
CT = 1500 pF
CT = 15000 pF
VCC = 5 V
TA = 25°C
RT − T iming Resistance − Ω
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
0
−1
−2
−3
−25 0 25 50
afosc − Oscillator Frequency Variation − %
1
2
OSCILLATOR FREQUENCY VARIATION
vs
FREE-AIR TEMPERATURE
3
75 100
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
VCC = 3.6 V
RT = 10 kΩ
CT = 330 pF
fosc = 200 kHz
TA − Free-Air Temperature − °C
osc
f
∆
fosc − Triangle Oscillator Frequency − Hz
osc
f
Figure 3 Figure 4
2.2
2
1.6
1.4
0.8
2.6
1.8
Triangle Waveform Swing Voltage − V
2.4
TRIANGLE WAVEFORM SWING VOLTAGE
vs
TIMING CAPACITANCE
1.2
1
VCC = 5 V
RT = 5.1 kΩ
TA = 25°C
CT − Timing Capacitance − pF
101102103104105
Triangle Waveform Period − uS
TRIANGLE WAVEFORM PERIOD
vs
TIMING CAPACITANCE
VCC = 5 V
RT = 5.1 kΩ
TA = 25°C
sµ
102
101
100
10−1
101102103104105
CT − Timing Capacitance − pF
Figure 5 Figure 6
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SGLS304A − JUNE 2005 − REVISED JUNE 2008
9
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TYPICAL CHARACTERISTICS
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
0
−10
− 20
− 30
− 25 0 25 50
10
20
REFERENCE OUTPUT VOLTAGE VARIATION
vs
FREE-AIR TEMPERATURE
30
75 100
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
VCC = 3.6 V
II(ref) = 1 mA
TA − Free-Air Temperature − °C
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
0
−10
− 20
− 30
− 25 0 25 50
10
20
REFERENCE OUTPUT VOLTAGE VARIATION
vs
FREE-AIR TEMPERATURE
30
75 100
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
VCC = 40 V
II(ref) = 1 mA
TA − Free-Air Temperature − °C
avref − Reference Output Voltage Variation − mV
ÁÁ
ÁÁ
ÁÁ
ÁÁ
VO(ref)
∆
avref − Reference Output Voltage Variation − mV
ÁÁ
ÁÁ
ÁÁ
ÁÁ
VO(ref)
∆
Figure 7 Figure 8
1.5
1
0.5
00 5 10 15 20 25
2
2.5
REFERENCE OUTPUT VOLTAGE
vs
SUPPLY VOLTAGE
3
30 35 40
TA = 25°C
VCC − Supply Voltage − V
0.8
0.7
0.6
− 25 0 25 50
Dropout Voltage Variation − V
0.9
1
DROPOUT VOLTAGE VARIATION
vs
FREE-TEMPERATURE
1.1
75 100
TA − Free-Air Temperature − °C
II(ref) = 1 mA
Vref − Reference Output Voltage − V
ÁÁ
ÁÁ
ÁÁ
VO(ref)
Figure 9 Figure 10

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
10 www.ti.com
TYPICAL CHARACTERISTICS
3
2
1
00123
VCE − Output Collector Voltage − V
4
5
UNDERVOLTAGE LOCKOUT
HYSTERESIS CHARACTERISTICS
6
45
TA = 25°CTA = −20°C
IO = 10 mA
7,10
8
RL
5 V
I = IO
VDE
TA = 85°C
VCC − Supply Voltage − V
ÁÁ
ÁÁ
ÁÁ
VCE
2
−25 0 25 50
Undervoltage Lockout Threshold Voltage − V
2.5
3
UNDERVOLTAGE LOCKOUT CHARACTERISTIC
3.5
75 100
Threshold Voltage −VTH
(Left Scale)
Threshold Voltage −VTL
(Left Scale)
Hysteresis Voltage
(Right Scale)
300
200
100
0
Undervoltage Lockout Hystersis Voltage − mV
TA − Free-Air Temperature − °C
3.25
2.75
2.25 50
150
250
Figure 11 Figure 12
1.20
1.15
1.10
− 25 0 25
Comparator Threshold Voltage − V
1.25
1.30
SHORT-CIRCUIT PROTECTION CHARACTERISTICS
50 75 100
Short-Circuit Protection
Latch Reset Supply Voltage
(Right Scale)
Short-Circuit Protection
Comparator Threshold Voltage
(Left Scale)
3
2.5
2
1.5
1
RS − Latch Reset Supply Voltage − V
TA − Free-Air Temperature − °C
Figure 13

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
11
www.ti.com
TYPICAL CHARACTERISTICS
9
6
3
00 50 100 150
tpe − Protection Enable Time − s
12
15
PROTECTION ENABLE TIME
vs
PROTECTION ENABLE CAPACITANCE
18
200 250
tpe
CPE − Protection Enable Capacitance − µF
+
−
Protection
Latch
SR
CPE U.V.L.O.
ERROR AMP 1
ERROR AMP 2
1.25 V
Short-circuit
Protection
Comparator 12 kΩ
15 16
SCP Vref
170 kΩVref Vref
Figure 14

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
12 www.ti.com
TYPICAL CHARACTERISTICS
1.75
1.5
1
0.75
0
2.25
1.25
1 k 10 k 100 k 1 M 10 M
Error Amp Maximum Output Voltage Swing − V
2
f − Frequency − Hz
ERROR AMP MAXIMUM OUTPUT VOLTAGE SWING
vs
FREQUENCY
0.5
0.25
VCC = 5 V
TA = 25°C
70
60
40
30
0
90
50
100 1 k 10 k 100 k 1 M 2 M
Open-Loop Voltage Amplification − dB
80
f − Frequency − Hz
OPEN-LOOP VOLTAGE AMPLIFICATION
vs
FREQUENCY
20
10
VCC = 5 V
TA = 25°C
Figure 15 Figure 16
−5
−20
1 k 10 k 100 k
G − Gain − dB
f − Frequency − Hz
GAIN (AMPLIFIER IN
UNITY-GAIN CONFIGURATION)
vs
FREQUENCY
10
1 M 10 M
5
0
−10
−15
VCC = 5 V
TA = 25°C
Figure 17

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
13
www.ti.com
TYPICAL CHARACTERISTICS
47 pF
470 pF
4700 pF
CX:
Phase Shift
(Right Scale)
Closed-Loop Gain
(Left Scale)
VCC = 5 V
Rref = 150 Ω
Cref = 470 pF
TA = 25°C
50
30
20
0
70
40
100 1 k 10 k 100 k 1 M
Closed-Loop Gain − dB
60
f − Frequency − Hz
CLOSED-LOOP GAIN AND PHASE SHIFT
vs
FREQUENCY
10
0°
−10°
−20°
−30°
−40°
−50°
−60°
−70°
−80°
−90°
Phase Shift
CxRref
Cref
Vref
39 kΩ
39 kΩ
+
−
Test Circuit
Figure 18

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
14 www.ti.com
TYPICAL CHARACTERISTICS
47 pF
470 pF
4700 pF
CX:
Phase Shift
(Right Scale)
Closed-Loop Gain
(Left Scale)
VCC = 5 V
Rref = 15 Ω
Cref = 470 pF
TA = 25°C
50
30
20
0
70
40
100 1 k 10 k 100 k 1 M
Closed-Loop Gain − dB
60
f − Frequency − Hz
CLOSED-LOOP GAIN AND PHASE SHIFT
vs
FREQUENCY
10
0°
−10°
−20°
−30°
−40°
−50°
−60°
−70°
−80°
−90°
Phase Shift
CxRref
Cref
Vref
39 kΩ
39 kΩ
+
−
Test Circuit
Figure 19

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
15
www.ti.com
TYPICAL CHARACTERISTICS
47 pF
470 pF
4700 pF
CX:
Phase Shift
(Right Scale)
Closed-Loop Gain
(Left Scale)
VCC = 5 V
Rref = 15 Ω
Cref = 470 pF
TA = 25°C
50
30
20
0
70
40
100 1 k 10 k 100 k 1 M
Closed-Loop Gain − dB
60
f − Frequency − Hz
CLOSED-LOOP GAIN AND PHASE SHIFT
vs
FREQUENCY
10
0°
−10°
−20°
−30°
−40°
−50°
−60°
−70°
−80°
−90°
Phase Shift
CxRref
Cref
Vref
39 kΩ
39 kΩ
+
−
Test Circuit
Figure 20

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
16 www.ti.com
TYPICAL CHARACTERISTICS
Phase Shift
(Right Scale)
Closed-Loop Gain
(Left Scale)
VCC = 5 V
Cref = 470 pF
TA = 25°C
50
30
20
0
70
40
100 1 k 10 k 100 k 1 M
Closed-Loop Gain − dB
60
f − Frequency − Hz
CLOSED-LOOP GAIN AND PHASE SHIFT
vs
FREQUENCY
10
0°
−10°
−20°
−30°
−40°
−50°
−60°
−70°
−80°
−90°
Phase Shift
Cref
Vref
39 kΩ
39 kΩ
+
−
Test Circuit
Figure 21

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
17
www.ti.com
TYPICAL CHARACTERISTICS
60
40
20
00510
Output Sink Current − mA
80
100
Collector Output Saturation Voltage − V
OUTPUT SINK CURRENT
vs
COLLECTOR OUTPUT SATURATION VOLTAGE
120
15 20
110
90
70
50
30
10
TA = −20°C
TA = 25°C
VCC = 3.6 V
TA = 85°C
Figure 22
MAXIMUM OUTPUT VOLTAGE SWING
vs
FREE-AIR TEMPERATURE
VO(ref) −0.01
VO(ref) −0.02
VO(ref) −0.03
VO(ref) −0.04
VO(ref) −0.05
VO(ref) −0.06
VO(ref) −0.07
1
0.9
0.8
0.7
0.6
0.5
−25 0 25 50 75 100
TA − Free-Air Temperature − °C
Maximum Output Voltage
Swing (Right Scale)
Maximum Output
Voltage Swing (Right Scale)
+
−RL
100 kΩ
Vvom − 1
33 kΩ
33 kΩ
VCC = 3.6 V
RL = 100 kΩ
VOM+1 = 1.25 V
VOM −1 = 1.15 V (Right Scale)
VOM −1 = 1.35 V (Left Scale)
Vref
TEST CIRCUIT
− Maximum Output Voltage Swing − VVOM
− Maximum Output Voltage Swing − VVOM
Figure 23

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
18 www.ti.com
TYPICAL CHARACTERISTICS
50
60
90
1000 0.5 1 1.5 2 2.5 3
Output Transistor “On” Duty Cycle − %
30
10
Dead-Time Input Voltage − V
OUTPUT TRANSISTOR ON DUTY CYCLE
vs
DEAD-TIME INPUT VOLTAGE
0
3.5 4
70
20
40
80
VCC = 3.6 V
RT = 10kΩ
CT = 330 pF
1
0.5
001020
ICC (Standby) − Standby Current − mA
2
STANDBY CURRENT
vs
SUPPLY VOLTAGE
30 40
1.5
ÁÁ
ÁÁ
CC
I
VCC − Supply Voltage − V
TA = 25°C
1.75
1.25
0.75
0.25
Figure 24 Figure 25
1
0.5
0
−25 0 25 50
ICC − Supply Current − mA
1.5
2
STANDBY CURRENT
vs
FREE-AIR TEMPERATURE
75 100
ÁÁ
ÁÁ
CC
I
T
A
− Free-Air Temperature − °C
Average Supply Current
VCC = 6 V, RT = 10 kΩ,
CT = 330 pF
Stand-By Current, VCC = 40 V, No Load
Stand-By Current, VCC = 3.6 V, No Load 600
400
200
0
−25 0 25 50
Maximum Continuous Power Dissipation − mW
800
1000
MAXIMUM CONTINUOUS POWER DISSIPATION
vs
FREE-AIR TEMPERATURE
1200
75 100
1100
900
700
500
300
100
16-Pin N Plastic Dip
16-Pin NS Plastic SO
Thermal Resistance
125°C/W
Thermal Resistance
250°C/W
TA − Free-Air Temperature
1.75
1.25
0.75
0.25
Figure 26 Figure 27

   
SGLS304A − JUNE 2005 − REVISED JUNE 2008
19
www.ti.com
APPLICATION INFORMATION
R7
R6 C4
470 Ω
1 µF
220 Ω
C2
R4
R3
33 kΩ
33 kΩ
470 Ω
150 Ω
220 kΩ
0.47 µF50 kΩ
R1
500 pF
pF
C5 R5 500
C1
87654321
910111213141516
330 pF
L1
R2
33 kΩ
33 kΩ
Vref
33 kΩ33 kΩ
470 Ω
470 Ω
L2
V
CC
Step-Up
Output
Step-Down
Output
TL1451A
NOTE A: Values for R1 through R7, C1 through C4, and L1 and L2 depend upon individual application.
Figure 28. High-Speed Dual Switching Regulator
PACKAGE OPTION ADDENDUM
www.ti.com 20-Oct-2011
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status (1) Package Type Package
Drawing Pins Package Qty Eco Plan (2) Lead/
Ball Finish MSL Peak Temp (3) Samples
(Requires Login)
TL1451AQPWRG4Q1 ACTIVE TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
TL1451AQPWRQ1 ACTIVE TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
(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) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
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 TL1451A-Q1 :
•Catalog: TL1451A
•Enhanced Product: TL1451A-EP
PACKAGE OPTION ADDENDUM
www.ti.com 20-Oct-2011
Addendum-Page 2
•Military: TL1451AM
NOTE: Qualified Version Definitions:
•Catalog - TI's standard catalog product
•Enhanced Product - Supports Defense, Aerospace and Medical Applications
•Military - QML certified for Military and Defense Applications
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