©2003 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.3
Features
• Programmable Output Voltage to 36 Volts
• Low Dynamic Output Impedance 0.20 Typical
• Sink Current Capability of 1.0 to 100mA
• Equivalent Full-Range Temperature Coefficient of
50ppm/°C Typical
• T emperature Compensated For Operation Over Full Rated
Operating Temperatur e Ra nge
• Low Output Noise Voltage
• Fast Turn-on Response
Description
The TL431/TL431Aare three-terminal adjustable regulator
series with a guaranteed thermal stability over applicable
temperature ranges. The output voltage may be set to any
value between V
REF
(approximately 2.5 volts) and 36 volts
with two external resistors These devices have a typical
dynamic output impedance of 0.2W 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 R egulator
TL431/TL431A
2
Internal Block Diagram
Absolute Maximum Ratings
(Operating temperature range applies unless otherwise specified.)
Recommended Operating Conditions
Parameter Symbol Value Unit
Cathode Voltage V
KA
37 V
Cathode Current Range (Continuous) I
KA
-100 ~ +150 mA
Reference Input Current Range I
REF
-0.05 ~ +10 mA
Power Dissipation
D, LP Suffix Package
P Suffix Package P
D
770
1000 mW
mW
Operating Temperature Range T
OPR
-25 ~ +85 °C
Junction Temperature T
J
150 °C
Storage Temperature Range T
STG
-65 ~ +150 °C
Parameter Symbol Min Typ Max Unit
Cathode Voltage V
KA
V
REF
-36V
Cathode Current I
KA
1.0 - 100 mA
TL431/TL431A
3
Electrical Characteristics
(T
A
= +25°C, unless otherwise specified)
•T
MIN
= -25
°C, T
MAX
= +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) ∆VREF/
∆TVKA=VREF, IKA=10mA
TMIN≤TA≤TMAX -4.5 17 -4.5 17 mV
Ratio of Chan ge in
Reference Input Voltage ∆VREF/
∆VKA IKA
=10mA
∆VKA=10V-
VREF - - 10 -2.7 - -1.0 -2.7 mV/V
to the Change in
Cathode Voltage ∆VKA=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 Rang e ∆IREF/∆T
IKA=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
Dynam ic Im ped an ce
(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 Circ uit fo r 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 Voltage
Figure 3. Change In Reference Input Voltage vs.
Cathode Voltage
Figure 5. Small Signal Voltage Amplification vs. Frequency
Figu re 2. Ca tho d e Cur r en t vs. Ca th ode Voltag e
Figure 4. Dynamic Impedance Frequency
Figure 6. Pulse Respon se
TL431/TL431A
6
Typical Application
Figure 10. Shunt Regulator Figure 11. Output Control for Three-
Termianl Fixed Regulator Figure 12 . High Current Shunt Regula-
tor
Figure 13 . Current Limit or Current S ource Figure 14. Constant-Current Sink
V
O
1R
1
R
2
-------+


V
ref
=
TL431/A
V
O
V
ref
1R
1
R
2
-------+


=
TL431/A
MC7805/LM7805
V
O
1R
1
R
2
-------+


V
ref
=
TL431/A
TL431/A TL431/A
TL431/TL431A
7
Mechanic al Dime nsions
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
+0.10
–0.05
0.38
+0.10
–0.05
TO-92
TL431/TL431A
8
Mechanic al Dime nsions
(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
Mechanic al Dime nsions
(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
8/4/03 0.0m 001
Stock#DSxxxxxxxx
2003 Fairchild Semiconductor Corporation
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or (b) support or sustain life, and (c) whose failure to
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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 syst em who se fai lure to pe rform can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effec tiv ene ss.
www.fairchildsemi.com
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Ordering Information
Product Number Output Voltage Tolerance Package Operating Temperature
TL431ACLP 1% TO-92
-25 ~ + 85
o
C
TL431ACD 8-SOP
TL431CLP 2% TO-92
TL431CP 8-DIP
TL431CD 8-SOP