©2001 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.1
Features
• Programmable outpu t volt age to 36 vol ts
• Low dynamic output impedance 0.20 typical
• Sink current capability of 1.0 to 100mA
• Equivalent full-range temp erature coefficient of 50ppm/
°C typical
• Temperature compensated for operation over full rated
operating temp erature range
• Low outpu t 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 VREF (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. Arode 3. Cath ode
1. Cathode 2. 3. 6. 7. Aro de
8. Ref 4. 5. NC
1
1
1
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 Voltage 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 Pa cka ge PD770
1000 mW
mW
Operating Temperature Range TOPR -25 ~ + 85 oC
Storage Temperature Range TSTG -65 ~ + 150 oC
Parameter Symbol Min Typ Max Unit
Cathode Voltage VKA VREF -36V
Cathode Current 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)
∆
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 -1.54
µ
A
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
µ
A
Minim um Cathod e 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
µ
A
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 Vol tage
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 Response
TL431/TL431A
6
Typical Application
Figure 10. Shunt Regulator Figure 11. Output Control for Three-
Termianl Fixed Regulator Figure 12. High Current Sh unt R egula-
tor
Figure 13 . Current Limit or Curr ent 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
+0.10
–0.05
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
10
Ordering Information
Product Number Output Voltage Tolerance Package Operating Temperature
TL431ACLP 1% TO-92
-25 ~ + 85 oC
TL431ACD 8-SOP
TL431CLP 2% TO-92
TL431CP 8-DIP
TL431CD 8-SOP
TL431/TL431A
11
TL431/TL431A
4/17/01 0.0m 001
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2001 Fairchild Semicond uctor Corporation
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user.
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