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KA431/KA431A/KA431L
Programmable Shunt Regulator
Features
Description
•
•
•
•
The KA431/KA431A/KA431L 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 (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 excellent replacement for zener diodes
in many applications.
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
• Temperature compensated for operation over full rated
operating temperature range
• Low output noise voltage
• Fast turn-on response
TO-92
1
1. Ref 2. Anode 3. Cathode
8-DIP
8-SOP
1
1
1.Cathode 2.3.4.5.7.NC
6.Anode 8.Ref
1.Cathode 2.3.6.7.Anode
4.5.NC 8.Ref
SOT-23F
3
1
2
1. Cathode 2. Ref 3. Anode
Internal Block Diagram
Rev. 1.0.4
©2001 Fairchild Semiconductor Corporation
KA431/KA431A/KA431L
Absolute Maximum Ratings
(Operating temperature range applies unless otherwise specified.)
Parameter
Symbol
Value
Unit
Cathode Voltage
VKA
37
V
Cathode Current Range (Continuous)
IKA
-100~ + 150
mA
IREF
0.05~ + 10
mA
PD
770
1000
mW
mW
TOPR
-25 ~ + 85
o
-65 ~ + 150
o
Reference Input Current Range
Power Dissipation
D, Z Suffix Package
DIP Package
Operating Temperature Range
Storage Temperature Range
TSTG
C
C
Recommended Operating Conditions
Parameter
2
Symbol
Min
Typ
Max
Unit
Cathode Voltage
VKA
VREF
-
36
V
Cathode Current
IKA
1.0
-
100
mA
KA431/KA431A/KA431L
Electrical Characteristics
(TA = +25°C, unless otherwise specified)
Parameter
Symbol
Reference Input
Voltage
VREF
Deviation of
Reference
Input Voltage
OverTemperature
Ratio of Change
in
Reference Input
Voltage
∆VREF/
∆T
∆VREF/
∆VKA
to the Change in
Cathode
Voltage
Conditions
VKA=VREF,
IKA=10mA
VKA=VREF,
IKA=10mA
TMIN≤TA≤TMAX
IKA
=10mA
∆VKA=10
V-VREF
Min.
KA431
KA431A
KA431L
Typ.
Max. Min. Typ. Max. Min.
Typ.
2.450 2.500
-
-
Max.
2.550 2.470 2.495 2.520 2.482 2.495 2.508
4.5
17
- 10
- 2.7
-
-
4.5
17
- 1.0
- 2.7
-
-
4.5
17
- 1.0
- 2.7
Unit
V
mV
mV/V
∆VKA=36
V-10V
-
-0.5
-2.0
-
-0.5
-2.0
-
-0.5
-2.0
IKA=10mA,
R1=10KΩ,R2=∞
-
1.5
4
-
1.5
4
-
1.5
4
µA
Deviation of
Reference
Input Current
Over Full
Temperature
Range
IKA=10mA,
R1=10KΩ,R2=∞
∆IREF/∆T
TA =Full Range
-
0.4
1.2
0.4
1.2
0.4
1.2
µA
Minimum
Cathode Current for
Regulation
IKA(MIN)
VKA=VREF
-
0.45
1.0
-
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
-
0.05
1.0
µA
VKA=VREF,
IKA=1 to 100mA
f ≥1.0KHz
-
0.15
0.5
-
0.15
0.5
-
0.15
0.5
Ω
Reference Input
Current
Dynamic
Impedance
IREF
ZKA
-
-
• TMIN= -25 oC, TMAX= +85 oC
3
KA431/KA431A/KA431L
Test Circuits
Figure 1. Test Circuit for VKA=VREF
Figure 3. Test Circuit for lKA(OFF)
4
Figure 2. Test Circuit for VKA≥VREF
KA431/KA431A/KA431L
Typical Perfomance Characteristics
Figure 1. Cathode Current vs. Cathode Voltage
Figure 2. Cathode Current vs. Cathode Voltage
Figure 3. Change In Reference Input Voltage vs.
Cathode Voltage
Figure 4. Dynamic Impedance Frequency
Figure 5. Small Signal Voltage Amplification vs. Frequency
Figure 6. Pulse Response
5
KA431/KA431A/KA431L
Typical Application
R
V O =  1 + ------1- V ref

R 
R
V O = V ref  1 + ------1-
R2
R
V O =  1 + ------1- V ref

R 
Figure 10. Shunt Regulator
Figure 11. Output Control for ThreeTermianl Fixed Regulator
Figure 12. High Current Shunt Regulator
2
Figure 13. Current Limit or Current Source
6
2
Figure 14. Constant-Current Sink
KA431/KA431A/KA431L
Mechanical Dimensions
Package
TO-92
+0.25
4.58 ±0.20
4.58 –0.15
14.47 ±0.40
0.46 ±0.10
1.27TYP
[1.27 ±0.20]
1.27TYP
[1.27 ±0.20]
+0.10
0.38 –0.05
(0.25)
+0.10
0.38 –0.05
1.02 ±0.10
3.86MAX
3.60 ±0.20
(R2.29)
7
KA431/KA431A/KA431L
Mechanical Dimensions (Continued)
Package
1.524 ±0.10
#5
2.54
0.100
5.08
MAX
0.200
7.62
0.300
3.40 ±0.20
0.134 ±0.008
+0.10
0.25 –0.05
+0.004
0~15°
8
0.010 –0.002
3.30 ±0.30
0.130 ±0.012
0.33
0.013 MIN
0.060 ±0.004
#4
0.018 ±0.004
#8
9.60
MAX
0.378
#1
9.20 ±0.20
0.362 ±0.008
(
6.40 ±0.20
0.252 ±0.008
0.46 ±0.10
0.79
)
0.031
8-DIP
KA431/KA431A/KA431L
Mechanical Dimensions (Continued)
Package
8-SOP
MIN
#5
1.80
MAX
0.071
3.95 ±0.20
0.156 ±0.008
5.72
0.225
0~
8°
+0.10
0.15 -0.05
+0.004
0.006 -0.002
MAX0.10
MAX0.004
6.00 ±0.30
0.236 ±0.012
0.41 ±0.10
0.016 ±0.004
#4
1.27
0.050
#8
5.13
MAX
0.202
#1
4.92 ±0.20
0.194 ±0.008
(
0.56
)
0.022
1.55 ±0.20
0.061 ±0.008
0.1~0.25
0.004~0.001
0.50 ±0.20
0.020 ±0.008
9
KA431/KA431A/KA431L
Mechanical Dimensions (Continued)
Package
1.30 ±0.10
0.40 ±0.03
2.40 ±0.10
0.45~0.60
0.20 MIN
SOT-23F
0.03~0.10
0.38 REF
0.40 ±0.03
+0.05
0.12 –0.023
0.96~1.14
0.97REF
2.90 ±0.10
0.95 ±0.03 0.95 ±0.03
1.90 ±0.03
10
0.508REF
KA431/KA431A/KA431L
Mechanical Dimensions (Continued)
Package
SOT-89
1.50 ±0.20
4.50 ±0.20
(0.40)
(1.10)
2.50 ±0.20
C0.2
4.10 ±0.20
(0.50)
1.65 ±0.10
0.50 ±0.10
0.40 ±0.10
0.40
+0.10
–0.05
1.50 TYP 1.50 TYP
11
KA431/KA431A/KA431L
Ordering Information
Product Number
Output Voltage Tolerance
Package
0.5%
8-SOP
KA431LZ
KA431LD
TO-92
KA431LMF
SOT-23F
KA431AZ
TO-92
KA431AD
1%
8-SOP
KA431AMF
SOT-23F
KA431
8-DIP
KA431Z
KA431D
Operating Temperature
2%
KA431MF
-25 ~ + 85 oC
TO-92
8-SOP
SOT-23F
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.
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.
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