www.a-power.com.tw

1

Advanced Power Electronics Corp.

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-25 and SOP-8

• RoHS Compliant & Halogen Free 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.

Ordering Information

Typical Application Circuit

++++++++

R2

R1

VOUTVIN

VOUT = (1+R1/R2)VREF

Precision Regulator

Cin Cout

AP431

AP431A

ADJUSTABLE PRECISION SHUNT REGULATOR

A P 4 3 1 A X - X

Package Reference Voltage

T : TO-92 N/NR : SOT-23 Y : SOT-25 M : SOP-8

Tolerance : A : +/- 0.5% B : +/- 1%

G: SOT-89

SOT-89

20130401V6.2

www.a-power.com.tw

2

Advanced Power Electronics Corp. AP431A

Block Diagram REF (R)

VREF

+

-

Anode (A)

Cat

hode

(C)

Symbol

Pin Configuration

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

12

5

4

1

3 REF

NC7

5

Cathode

Cathode

Cathode

NC

Anode 12

5

4

1

3

REF

NCCathode

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

www.a-power.com.tw

3

Advanced Power Electronics Corp.

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-25 Package……………………...…………….………….………..0.25W SOP-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 2.520Reference 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/VRatio 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) KAZ 0.2 0.5 Ω

VMAX

VMIN

TI T2TEMPERATURE

VDEV = VMAX - VMIN

SOP-89 Package............................................................................... 0.5W

www.a-power.com.tw

4

Advanced Power Electronics Corp.

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 ……………………..……………….. ( ) Cppm

°

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

KAKA I

VZ∆∆

=

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:

)R2R1(1Z

ivZ KA

'KA +

∆∆= ≈

Test Circuits

Input

VREF

VKA

IKA

Fig1. Test Circuit for VKA= VREF

IN

VREF

R1

R2

IREF

Note:VKA=VREF(1+R1/R2)+IREF× R1

IKA

VKA

Fig2. Test circuit for VKA＞VREF

IN

VKA

IZ(OFF)

Fig3. Test Circuit for off-state Current

www.a-power.com.tw

5

Advanced Power Electronics Corp.

AP431A

Typical Performance Characteristics

Cathode current Vs Cathode Voltage

-100

0

100

-1.5 -0.5 0.5 1.5 2.5Cathode Voltage(v)

Cat

hode

cur

rent

(mA

)

VKA=VrefTa=25oC

Cathode current (uA) Vs Cathode Voltage

-1Cathode Voltage(v)

Cat

hode

cur

rent

(uA

)

-200

200

400

600

0

-0.5 0 0.5 1 1.5 2 2.5

VKA=VrefTa=25oC

Reference Voltage Vs Free-Air Temperature

Free-Air Tempeture (oC)

Ref

eren

ce V

olta

ge(m

V)

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(oC)

Ref

eren

ce in

put c

urre

nt (u

A)

1

1.2

1.4

1.6

1.8

2

-50 -25 0 25 50 75 100 125

R1=10KIKA=10mA

Change in Reference Voltage vs Cathode Voltage

0 5 10 15 20 25 30Cathode Voltage (V)

Cha

nge

in R

efer

ence

Vol

tage

(mv)

-12

-10

-8

-6

-4

-2

0

IKA=10mATa=25oC

www.a-power.com.tw

6

Advanced Power Electronics Corp.

AP431A

Typical Performance Characteristics(Continued)

+ - +

-

Output

GND

15KΩ

8.25KΩ

9µF

IKA 232Ω

TEST CIRCUIT FOR VOLTAGE AMPLIFICATION

SMALL-SIGNAL VOLTAGE AMPLIFICATION vs. FREQUENCY

0

10

20

30

40

50

60

1K 10K 100K 1M 10Mf-Frequency-Hz

AV-

Sm

all S

igna

l Vol

tage

Am

plifi

catio

n (d

B)

IKA=10mATA=25oC

+

-

I KA

GND

Output1KΩ

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∣—

Ref

eren

ce Im

peda

nce—Ω IKA=10mA

TA=25oC

www.a-power.com.tw

7

Advanced Power Electronics Corp.

AP431A

PULSE RESPONSE

0

1

2

3

4

5

6

-1 0 1 2 3 4 5 6 7

t-Time-µ S

Inpu

t and

Out

put V

olta

ge-V

Input

OutputGND

Output220Ω

50Ω

TEST CIRCUIT FOR PULSE RESPONSE

PulseGeneratorf=100kHz

TA=25oC

+

-

150Ω

I KA

VBATTCL

TEST CIRCUIT FOR CURVE A

+

-

CL

R1=10KΩ

R2

I KA150Ω

VBATT

TEST CIRCUIT FOR CURVE B, C, AND DThe areas under the curves represent conditions that may cause thedevice to oscillate. For curves B, C, and D, R2 and V+ were adjustedto establish the initial V KA and IKA conditions with CL=0.VBATT andCL 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 10CL-Load Capacitance-µF

I KA-

Cat

hode

Cur

rent

-mA

A VKA=Vref

B VKA=5VC VKA=10VD VKA=15V

A

B

C

D

Stable

Stable

TA=25oC

www.a-power.com.tw

8

Advanced Power Electronics Corp.

AP431A

Application Examples

VIN

+

Low Limit VREF(1 + R1B/R2B) +VBEHigh Limit VREF(1 + R1A/R2A)

R1A R1B

R2A R2B VBE

Output ON whenLow Limint < VIN< High Limit

Fig.10 Over-Voltage / Under-Voltage Protection Circuit

VIN

RCL IOUT

IOUT = VREF / RCL

Fig.6 Current Limiter or Current Source

IOUTVIN

IOUT = VREF / RS

RS

Fig.7 Constant-Current Sink

Fig.4 Voltage Monitor Fig.5 Delay Timer

VOUT = (1 + R1/R2) x VREF

VIN

R1

R2

Fig.8 Higher-Current Shunt Regulator

VOUT VINPUSE

R1

R2

LIMIT (1 + R1/R2) x VREF

Fig.9 Crow Bar

VOUT

VIN

ONOFF

R

+

VINDelay = RC x ln( VIN -VREF)LED on when Low Limit＜VIN＜High Limit

Low Limit ≈ VREF (1+R1B/R2B)High Limit ≈ VREF (1+R1A/R2A)

R1A

R2A

VIN

R1B

R2B

Advanced Power Electronics Corp. AP431AMARKING INFORMATIONSO-8

SOT-23-5L

SOT-23

SOT-89

9

431AMYWWSSS

Part Number

Date Code (YWWSSS) Y：Last Digit Of The Year WW：Week SSS：Sequence

Package Code

R6&XX

Part Number :AP431AY : R6AP431AY5 : R65

ID Code : Internal

R6&XX

Part Number :AP431AN : R6AP431ANR : R6R

ID Code : Internal

431A

Part Number

YWWS Date Code (YWWS) Y:Year WW：Week

S：Sequence

Advanced Power Electronics Corp. AP431AMARKING INFORMATIONTO-92

10

431A

YWWS

Part Number

Date Code (YWWS) Y:Year WW：Week

S：Sequence