©2011 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.4
Features
• Programmable Output Voltage to 36 Volts
• Low Dynamic Outpu t Impedance 0.2Ω Typical
• Sink Current Capability of 1.0 to 100mA
• Equivalent Full-Range Temperature Coefficient of
50ppm/°C Typical
• Temperature Compensated For Operation Over Full Rated
Operating Temperature Range
• Low Output Noise Voltage
• Fast Turn-on Response
Description
The TL431/TL431A are three-terminal adjustable regulator
series with a guaranteed thermal stability over applicable
temperature ranges. The output voltage may be set to any
value between VREF (appro ximately 2.5 volts) and 36 volts
with two external resistors These devices have a typical
dynamic output impedance of 0.2Ω. Active output circuitry
provides a very sharp turn-on characteristic, making these
devices excel lent replacement for zener diodes in many
applications.
TO-92
8-DIP
8-SOP
1. Ref 2. Anode 3. Cathode
1. Cathode 2. 3. 6. 7. Anode
8. Ref 4. 5. NC
1
1
1
1.Cathode 2.3.4.5.7.NC
6.Anode 8.Ref
TL431/TL431A
Programmable Shunt Regulator
TL431/TL431A
2
Internal Block Diagram
Absolute Maximum Ratings
(Operating temperature range applies unless otherwise specified.)
Recommended Operating Conditions
Parameter Symbol Value Unit
Cathode Volt ag e VKA 37 V
Cathode Current Range (Continuous) IKA -100 ~ +150 mA
Reference Input Current Range IREF -0.05 ~ +10 mA
Power Dissipation
D, LP Suffix Package
P Suffix Package PD770
1000 mW
mW
Operating Temperature Range TOPR -25 ~ +85 °C
Junction Temperature TJ150 °C
Storage Temperature Range TSTG -65 ~ +150 °C
Parameter Symbol Min Typ Max Unit
Cathode Volt ag e VKA VREF -36V
Cathode Curr en t IKA 1.0 - 100 mA
+
-
TL431/TL431A
3
Electrical Characteristics
(TA = +25°C, unless otherwise specified)
•T
MIN= -25 °C, TMAX= +85 °C
Parameter Symbol Conditions TL431 TL431A Unit
Min. Typ. Max. Min. Typ. Max.
Reference Input Voltage VREF VKA=VREF, IKA=10mA 2.440 2.495 2.550 2.470 2.495 2.520 V
Deviation of Reference
Input Voltage Over-
Temperature (Note 1)
ΔVREF/
ΔTVKA=VREF, IKA=10mA
TMIN≤TA≤TMAX -4.517 -4.517mV
Ratio of Change in
Reference Input Voltage
to the Change in
Cathode Voltage
ΔVREF/
ΔVKA IKA
=10mA
ΔVKA=10V-
VREF - - 1.0 -2.7 - -1.0 -2.7 mV/V
ΔVKA=36V-
10V - -0.5 -2.0 - -0.5 -2.0
Reference Input Current IREF IKA=10mA,
R1=10KΩ,R2=∞-1.54 -1.54μA
Deviation of Reference
Input Current Over Full
Temperature Range ΔIREF/ΔTIKA=10mA,
R1=10KΩ,R2=∞
TA =Full Range - 0.4 1.2 - 0.4 1.2 μA
Minimum Cathode Cur-
rent for Regulation IKA(MIN) VKA=VREF - 0.45 1.0 - 0.45 1.0 mA
Off - Stage Cathode
Current IKA(OFF) VKA=36V, VREF=0 - 0.05 1.0 - 0.05 1.0 μA
Dynamic Impedance
(Note 2) ZKA VKA=VREF,
IKA=1 to 100mA
f ≥1.0KHz - 0.15 0.5 - 0.15 0.5 Ω
TL431/TL431A
4
Test Circuits
Figure 1. Test Circuit for VKA=VREF Figure 2. Test Circuit for VKA≥VREF
TL431/A TL431/A
TL431/A
Figure 3. Test Circuit for lKA(OFF)
TL431/TL431A
5
Typical Perfomance Characteristics
Figure 1. Cathode Current vs. Cathode Volta ge
Figure 3. Change In Reference Inpu t Voltage vs.
Cathode Voltage
Figure 5. Small Signal Voltage Amplification vs. Frequency
Figure 2. Cathode Current vs. Cath ode Voltage
Figure 4. Dyna mi c Impedance Frequency
Figure 6. Pulse Response
TL431/TL431A
6
Typical Application
Figure 10. Shunt Regulator Figure 11. Output Control for Three-
Termianl Fi xed Regulator Figure 12. High Current Shunt Regula-
tor
Figure 13. Current Limit or Current Source Figure 14. Constant-Current Sink
VO1R1
R2
-------
+
⎝⎠
⎛⎞
Vref
=
TL431/A
VOVref 1R1
R2
-------
+
⎝⎠
⎛⎞
=
TL431/A
MC7805/LM7805
VO1R1
R2
-------
+
⎝⎠
⎛⎞
Vref
=
TL431/A
TL431/A TL431/A
TL431/TL431A
7
Mechanical Dimensions
Package
0.46
±0.10
1.27TYP
(R2.29)
3.86MAX
[1.27
±0.20
]1.27TYP
[1.27
±0.20
]
3.60
±0.20
14.47
±0.40
1
.02
±0.10
(0.25) 4.58
±0.20
4.58
+0.25
–0.15
0.38
+0.1
0
–0.0
5
0.38
+0.10
–0.05
TO-92
TL431/TL431A
8
Mechanical Dimensions (Continued)
Package
6.40 ±0.20
3.30 ±0.30
0.130 ±0.012
3.40 ±0.20
0.134 ±0.008
#
1
#
4#5
#8
0.252 ±0.008
9.20 ±0.20
0.79
2.54
0.100
0.031
(
)
0.46 ±0.10
0.018 ±0.004
0.060 ±0.004
1.524 ±0.10
0.362 ±0.008
9.60
0.378 MAX
5.08
0.200
0.33
0.013
7.62
0~15°
0.300
MAX
MIN
0.25
+0.10
–0.05
0.010
+0.004
–0.002
8-DIP
TL431/TL431A
9
Mechanical Dimensions (Continued)
Package
4.92 ±0.20
0.194 ±0.008
0.41 ±0.10
0.016 ±0.004
1.27
0.050
5.72
0.225
1.55 ±0.20
0.061 ±0.008
0.1~0.25
0.004~0.001
6.00 ±0.30
0.236 ±0.012
3.95 ±0.20
0.156 ±0.008
0.50 ±0.20
0.020 ±0.008
5.13
0.202 MAX
#1
#4 #5
0~8°
#8
0.56
0.022
()
1.80
0.071
MAX0.10
MAX0.004
MAX
MIN
+
0.10
-0.05
0.15+
0.004
-0.002
0.006
8-SOP
TL431/TL431A
2/22/11 0.0m 001
Stock#DS400301
© 2011 Fairchild Semiconductor Corporation
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES
OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body,
or (b) support or sustain life, and (c) whose failure to
perform when properly used in accordance with
instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of the
user.
2. A critical component in any component of a life support
device or system whose failure to perform can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
www.fairchildsemi.com
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY
PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY
LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER
DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.
Ordering Information
Product Number Output Voltage Tolerance Package Operating Temperature
TL431ACLP 1% TO-92
-25 ~ + 85oC
TL431ACD 8-SOP
TL431CLP 2% TO-92
TL431CP 8-DIP
TL431CD 8-SOP
