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Advanced Power
Electronics Co rp. AP431A
Features
• Precision reference voltage
AP431A : 2.495V ± 0.5%
• Sink current capability: 200mA
• Minimum cathode current for regulation: 300μA
• Equivalent full-range temp coefficient: 30 ppm/oC
• Fast turn-on response
• Low dynamic output impedance: 0.2Ω
• Programmable output voltage to 36V
• Low output noise.
• Packages: TO-92,SOT-23, SOT-23-5L(SOT-25)
• Halogen Free & RoHS Compliant Product
Description
The AP431A are 3-terminal adjustable precision
shunt regulators with guaranteed temperature
stability over the applicable extended commercial
temperature range. The output voltage may be set at
any level greater than 2.495V(VREF) up to 36V merely
by selecting two external resistors that act as a
voltage divider network. These devices have a
typical output impedance of 0.2Ω. Active output
circuitry provides very sharp turn-on characteristics,
making these devices excellent improved
replacements for Zener diodes in many applications.
The precise (+/-) 1% Reference voltage tolerance of
the AP431A make it possible in many applications to
avoid the use of a variable resistor, consequently
saving cost and eliminating drift and reliability
problems associated with it.
Orderi ng I nfor mation
Typical Application Circuit
+
++
+
+
++
+
R2
R1
V
OUT
V
IN
V
OUT
= (1+R1/R2)V
REF
Precision Regulator
C
in
C
out
AP431
AP431A
ADJUSTABLE PRECISION SHUNT REGULATOR
AP431AX-X-HF
Package Reference Voltage
T : TO-92
N/NR : SOT-23
Y : SOT-23-5L(SOT-25)
M : SO-8
Tolerance :
A : +/- 0.5%
B : +/- 1%
G: SOT-89
and SO-8 SOT-89
201210046
Halogen Free & RoHS product
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Electronics Co rp. AP431A
Block Diagram
REF (R)
V
REF
+
-
Anode (A)
Cathode (C)
Symbol
Pin Configur ation
Order Number Pin Configuration ( Top View )
AP431AT
( TO-92 )
3 Cathode
2 Anode
1 REF
AP431AM
( SO-8 )
1
2
3
4
8
6
Anode
Anode
NC
Anode
Anode
NC
REF
Order Number Pin Configuration ( Top View )
AP431AN
( SOT-23 )
Cathode
Anode
REF
AP431AY
( SOT-23-5L )
NC Anode
3
2
1
1
2
5
4
1
3
REF
NC
7
5
Cathode
Cathode
Cathode
NC
Anode
1
2
5
4
1
3
REF
NC
Cathode
AP431AY5
( SOT-23-5L )
Anode
REF
2
3
1
Cathode
AP431AG
( SOT-89 )
2
Cathode (C)
REF (R)
Anode (A)
AP431ANR
( SOT-23 )
Anode
REF
3
2
1 Cathode
Rthja=160oC/W
Rthjl=60oC/W
Rthja=208oC/W
Rthjc=50oC/W
Rthja=250oC/W
Rthjc=110oC/W
Rthja=500oC/W
Rthjc=180oC/W
Rthja=500oC/W
Rthjc=180oC/W
Rthja=500oC/W
Rthjc=180oC/W
Rthja=500oC/W
Rthjc=180oC/W
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Electronics Co rp. AP431A
Absolute Maximum Ratings
Cathode Voltage ………………………………......….........................…...……………………………...……….36V
Continuous Cathode Current ………………………….…….............…................…………….... -10mA ~ 250mA
Reference Input Current Range ……………..………..............…….................................………….…....... 10mA
Operating Temperature Range ………….…………..…….…….....………………...........………......-40oC ~ 85oC
Lead Temperature………………………….………….…….…………....…………………….........…............ 260oC
Storage Temperature ……………………………......…....….............………………..……...…....... -65oC ~ 150oC
Power Dissipation (Notes 1. 2) TO-92 Package ….…………..………………………....………….....… 0.78W
SOT-23 Package .…...…………..…………….......…………………… 0.25W
SOT-23-5L Package…………………...…………….………….……… 0.25W
SO-8 Package……………….………………………………………….. 0.6W
Note 1: TJ, max =150oC
Note 2: Ratings apply to ambient temperature at 25oC
Electrical Characteristics (Ta=25oC , unless otherwise specified.)
PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT
-B 2.470 2.495 2.520
Reference voltage VKA = VREF,
I KA = 10mA (Fig.1) -A VREF 2.482 2.507 V
Deviation of Reference input voltage
over temperature (Note 3)
VKA = VREF, IKA = 10mA,
Ta = Full range (Fig.1) VREF 8.0 20 mV
VKA = 10V
~VREF ∆VREF -1.4 -2.0 mV/V
Ratio of the change in Reference
voltage to the change in Cathode
voltage
IKA = 10mA (Fig.2)
VKA= 36V ~10V ∆VKA -1 -2 mV/V
Reference input current R1 = 10KΩ,R2 = ∞ IKA= 10mA
(Fig.2) IREF 1.4 3.5 µA
Deviation of Reference input current
over temperature
R1 = 10KΩ,R2 = ∞ IKA = 10mA
Ta = Full range (Fig.2) αIREF 0.4 1.2 µA
Minimum Cathode current for
regulation VKA = VREF (Fig.1) IKA(MIN) 0.19 0.5 mA
Off-state current VKA = 36V, VREF = 0V (Fig.3) IKA(OFF) 0.1 1.0 µA
Dynamic output impedance (Note 4) V KA = VREF
Frequency ≤ 1KHz (Fig.1) KA
Z 0.2 0.5 Ω
V
MAX
V
MIN
T
I
T
2
TEMPERATURE
V
DEV
= V
MAX
- V
MIN
SOT-89 Package............................................................................... 0.5W
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Electronics Co rp. AP431A
Note 3. Deviation of reference input voltage, VDEV, is defined as the maximum variation of the reference over
the full temperature range.
The average temperature coefficient of the reference input voltage αVREF is defined as:
12
6
REF
DEV
REF TT
10)
C)(25V
V
(
V−
⋅
°
=α ……………………..……………….. ( )
C
ppm°
Where:
T2 – T1 = full temperature change.
αVREF can be positive or negative depending on whether the slope is positive or negative.
Note 4. The dynamic output impedance, RZ, is defined as:
KA
KA
KA I
V
Z∆
∆
=
When the device is programmed with two external resistors R1 and R2 (see Figure 2.), the dynamic output
impedance of the overall circuit, is defined as:
)
R2
R1
(1Z
i
v
ZKA
'
KA +
∆
∆
=≈
Test Circuits
Input
V
REF
V
KA
I
KA
Fig1. Test Circuit for V
KA
= V
REF
IN
V
REF
R1
R2
I
REF
Note:V
KA
=V
REF
(1+R1/R2)+I
REF×
R1
I
KA
V
KA
Fig2. Test circuit for V
KA
＞
V
REF
IN
V
KA
I
Z(OFF)
Fig3. Test Circuit for off-state Current
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Electronics Co rp. AP431A
Typical Performance Characteristics
Cathode current Vs Cathode Voltage
-100
0
100
-1.5 -0.5 0.5 1.5 2.5
Cathode Voltage(v)
Cathode current(mA)
V
KA
=Vref
Ta=25
o
C
Cathode current (uA) Vs Cathode Voltage
-1
Cathode Voltage(v)
Cathode current(uA)
-200
200
400
600
0
-0.5 0 0.5 11.5 2 2.5
V
KA
=Vref
Ta=25
o
C
Reference Voltage Vs Free-Air Temperature
Free-Air Tempeture (
o
C)
Reference Voltage(mV)
2480
2485
2490
2495
2500
-40 80-30 -20 -10 0 10 20 30 40 50 60 70
Reference input current Vs free Temperature
Free-Air Temperature(
o
C)
Reference input current (uA)
1
1.2
1.4
1.6
1.8
2
-50 -25 0 25 50 75 100 125
R1=10K
I
KA
=10mA
Change in Reference Voltage vs Cathode Voltage
0 5 10 15 20 25 30
Cathode Volta
g
e
(
V
)
Change in Reference Voltage (mv)
-12
-10
-8
-6
-4
-2
0
I
KA
=10mA
Ta=25
o
C
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Advanced Power
Electronics Co rp. AP431A
Typical Performance Characteristics(Continued)
+
-
+
-
Output
GND
15KΩ
8.25KΩ
9µF
I
KA
232Ω
TEST CIRCUIT FOR VOLTAGE AMPLIFICATION
SMALL-SIGNAL VOLTAGE AMPLIFICATION vs. FREQUENCY
0
10
20
30
40
50
60
1K 10K 100K 1M 10M
f-Frequency-Hz
AV-Small Signal Voltage Amplification (dB)
I
KA
=10mA
T
A
=25
o
C
+
-
IKA
GND
Output
1KΩ
50Ω
TEST CIRCUIT FOR REFERENCE IMPEDANCE
REFERENCE IMPEDANCE vs. FREQUENCY
0.1
1
10
100
1K 10K 100K 1M 10M
f-Frequency-Hz
∣ZK
A
∣—Reference Impedance —Ω
I
KA
=10mA
T
A
=25
o
C
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Electronics Co rp. AP431A
PULSE RESPONSE
0
1
2
3
4
5
6
-101234567
t-Time-µ S
Input and Output Voltage-V
Input
Output
GND
Output
220Ω
50Ω
TEST CIRCUIT FOR PULSE RESPONSE
Pulse
Generator
f=100kHz
T
A
=25
o
C
+
-
150Ω
IKA
V
BATT
C
L
TEST CIRCUIT FOR CURVE A
+
-
C
L
R1=10KΩ
R2
IKA
150Ω
V
BATT
TEST CIRCUIT FOR CURVE B, C, AND D
The areas under the curves represent conditions that may cause the
device to oscillate. For curves B, C, and D, R2 and V+ were adjusted
to establish the initial V
KA
and I
KA
conditions with C
L
=0.V
BATT
and
C
L
were then adjusted to determine the ranges of stability.
STABILITY BOUNDARY CONDITIONS
†
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10
C
L
-Load Capacitance-µF
I
KA
-Cathode Current-mA
A
V
KA
=V
ref
B V
KA
=5V
C V
KA
=10V
D V
KA
=15V
A
B
C
D
Stable
Stable
TA=25
o
C
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Electronics Co rp. AP431A
Application Examples
V
IN
+
Low Limit V
REF
(1 + R1B/R2B) +V
BE
High Limit V
REF
(1 + R1A/R2A)
R1A R1B
R2A R2B V
BE
Output ON when
Low Limint < V
IN
< High Limit
Fig.10 Over-Voltage / Under-Voltage Protection Circuit
V
IN
R
CL
I
OUT
I
OUT
= V
REF
/ R
CL
Fig.6 Current Limiter or Current Source
I
OUT
V
IN
I
OUT
= V
REF
/ R
S
R
S
Fig.7 Constant-Current Sink
Fig.4 Voltage Monitor Fig.5 Delay Timer
V
OUT
= (1 + R1/R2) x V
REF
V
IN
R1
R2
Fig.8 Higher-Current Shunt Regulator
V
OUT
V
IN
PUSE
R1
R2
L
IMIT
(1 + R1/R2) x V
REF
Fig.9 Crow Bar
V
OUT
V
IN
ON
OFF
R
+
V
IN
Delay = RC x ln( V
IN
-V
REF
)
LED on when Low Limit
＜
V
IN
＜
High Limit
Low Limit
≈
V
REF
(1+R1B/R2B)
High Limit
≈
V
REF
(1+R1A/R2A)
R1A
R2A
V
IN
R1B
R2B
Advanced Power
Electronics Corp. AP431A
MARKING INFORMATION
SO-8
SOT-23-5L
SOT-23
SOT-89
9
431AM
YWWSSS
Part Number
Date Code (YWWSSS)
Y：Last Digit Of The Year
WW：Week
SSS：Sequence
Package Code
R6&XX
Part Number :
A
P431AY : R6
A
P431AY5 : R65
ID Code : Internal
R6&XX
Part Number :
A
P431AN : R6
P431ANR : R6R
ID Code : Internal
4
3
1
A
Part Number
YWW
S
Date Code (YWWS)
Y:Year
WW：Week
S
：
Sequence
Advanced Power
Electronics Corp. AP431A
MARKING INFORMATION
TO-92
10
431A
Y
WWS
Part Number
Date Code (YWWS)
Y:Year
WW：Week
S
：
Sequence