Datasheet TL431CX, TL431CZ, TL431CU, TL431ACZ, TL431ACX Datasheet (AIC)

AIC431/TL431A/TL431

Adjustable Precision Shunt Regulators

Analog Integrations Corporation 4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC

www.analog.com.tw

DS-431-06 May 31, 01 TEL: [phone] FAX: [phone]

n

FEATURES

l Unconditionally Stable.
l Precision Reference Voltage.

AIC431 :2.495V ±0.5%
TL431A :2.495V ±1.0%
TL431 :2.495V ±1.6%

l Sink Current Capability: 200mA.
l Minimum Cathode Current for Regulation: 250µA.
l Equivalent Full-Range Temperature Coefficient:

50 ppm/°C.

l Fast Turn-On Response.
l Low Dynamic Output Impedance: 0.08Ω.
l Adjustable Output Voltage.
l Low Output Noise.
l Space Saving SOT-89, SOT-23, TO-92 and SO8

packages.

n

TYPICAL APPLICATION CIRCUIT

V

IN

AIC431

+

V

OUT

R1

R2

+

V

OUT

=(1+R1/R2)V

REF

Precision Regulator

n

DESCRIPTION

The AIC431/TL431A/TL431 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 (V

REF

) up to 30V merely
by selecting two external resistors that act as
a voltage divider network. These devices have
a typical output impedance of 0.08Ω. Active
output circuitry provides a very sharp turn-on
characteristics, making these devices excel­lent improved replacements for zener diodes
in many applications.

The precise ±0.5% reference voltage toler­ance of the AIC431 makes 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.

AIC431/TL431A/TL431

2

n

ORDERING INFORMATION

ORDER NUMBER PIN CONFIGURATION

AIC431 CX
TL431A CX

TL431

CX

PACKAGING TYPE
S: SMALL OUTLINE
U: SOT-23
X: SOT-89
Z: TO-92

AIC431CX
TL431ACX
TL431CX
(SOT-89)

FRONT VIEW
1: VREF
2: ANODE
3: CATHODE

1
2
3

1 2 3

AIC431CZ
TL431ACZ
TL431CZ
(TO-92)

FRONT VIEW
1: VREF
2: ANODE
3: CATHODE

ANODE

REF
ANODE

NC

ANODE

ANODE

NC

CATHOD

1

3
4

2

8

6
5

7

AIC431CS
TL431ACS
TL431CS
(SO-8)

TOP VIEW

AIC431CUN
TL431ACUN
TL431CUN
(SOT-23)

FRONT VIEW
1: CATHODE
2: VREF
3: ANODE

1

3

2

AIC431CUS
TL431ACUS
TL431CUS
(SOT-23)

FRONT VIEW
1: VREF
2: CATHODE
3: ANODE

3

1

2

n

ABSOLUTE MAXIMUM RATINGS

Cathode Voltage ........……………...............……………..………...............................30V

Continuous Cathode Current ...................………….……...................... -10mA ~ 250mA

Reference Input Current Range .......…………........……..........…………………… 10mA

Operating Temperature Range .......………….........……….........……………. -40°C ~ 85°C

Lead Temperature .......…………..................………………..………………………. 260°C

Storage Temperature .......…………..................……………..…………….. -65°C ~ 150°C

Power Dissipation (Notes 1, 2) SOT-89 Package .........…………...... 0.80W

TO-92 Package ….......…………....... 0.78W

Note 1: T

J, max

= 150°C.

Note 2: Ratings apply to ambient temperature at 25°C.

AIC431/TL431A/TL431

3

n

TEST CIRCUITS

V

REF

I

REF

I

Z

V

Z

I

L

IN

AIC431

R2

R1

V

REF

I

REFIZVZ

IN

I

L

AIC431

Note: VZ=V

REF

(1+R1/R2)+I

REF

xR1

Fig. 1 Test Circuit for VZ=V

REF

Fig. 2 Test circuit for VZ>V

REF

IN

VZ

IZ(OFF)

AIC431

Fig. 3 Test circuit for off-state Current

n

ELECTRICAL CHARACTERISTICS

(Ta=25°C, unless otherwise spec ified.)

PARAMETER TEST CONDITIONS

SYMBOL

MIN. TYP. MAX. UNIT

VZ=V

REF

, AIC431 2.482 2.495 2.508

IL =10mA (Fig. 1) TL431A 2.470 2.495 2.520

Reference Voltage

TL431

V

REF

2.455 2.495 2.535

V

Deviation of Reference
Input Voltage Over
Temperature (Note 3)

V

Z

= V

REF

, I

L

=10mA,

Ta = 0°C~ +85°C (Fig. 1)

V

DEV

9.0 20 mV

Ratio of the Change in Refer­ence Voltage to

IZ=10mA ∆VZ=10V-V

REF

-0.5 -2.0 mV/V

the Change in Cathode volt­age

(Fig. 2) ∆VZ=30V-10V

∆V

REF

∆V

Z

-0.35 -1.5 mV/V

Reference Input Current R1 =10KΩ, R2= ∞,

I

L

=10mA (Fig. 2)

I

REF

0.8 3.5 µA

AIC431/TL431A/TL431

4

Deviation of Reference Input
Current over Temperature

R1 =10KΩ, R2= ∞,
I

L

=10mA

Ta =-20°C ~ +85°C (Fig. 2)

αI

REF

0.3 1.2 µA

AIC431/TL431A/TL431

5

n

ELECTRICAL CHARACTERISTICS

(Continued)

PARAMETER TEST CONDITIONS

SYMBOL

MIN. TYP. MAX. UNIT

Minimum Cathode current for
Regulation

VZ=V

REF

(Fig. 1) I

Z(MIN)

0.25 0.5 mA

Off-State Current VZ=20V, V

REF

=0V (Fig. 3) I

Z(OFF)

0.1 1.0 µA

Dynamic Output Impedance

(Note 4)

VZ=V

REF

Frequency= 0Hz (Fig. 1)

R

Z

0.08 0.3 Ω

T

2

T

1

V

MAX

VDEV = VMAX-VMIN

V

MIN

TEMPERATURE

Note 3. Deviation of reference input voltage, V

DEV

, is de­fined as the maximum variation of the reference input
voltage over the full temperature range.

The average temperature coefficient of the reference in­put voltage, αV

REF

is defined as:

T1T2

10

C)25 (atV

V

T1T2

6

10

C)25 (atV

V-V

C

ppm

V

6

REF

DEV

REF

MINMAX

REF

−











°

±

=

−











°

±

=

°

∆

Where:
T

2−T1

=full temperature change.

αV

REF

can be positive or negative depending on

whether the slope is positive or negative.

Example: V

DEV

= 9.0mV, V

REF

= 2495mV,

T

2−T1

= 70°C, slope is negative.

C50ppm/V

C70

6

10

2495mV

9.0mV

REF °−=













=

°

α

Note 4. The dynamic output impedance, Rz, is de-
fined as:

RZ =

Z

ZV

I∆

∆

When the device is programmed with two external re­sistors, R1 and R2, (see Fig. 2), the dynamic output
impedance of the overall circuit, is defined as:

[

]

R2

R1

1Rz

Iz

Vz

zr +≅

∆

∆

=

n

TYPICAL PERFORMANCE CHARACTERISTICS

-1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0

-600

-400

-200

0

200

400

600

800

1000

I

Z(MIN)

VZ =V

REF

TA =25°C

Cathode Current vs Cathode Voltage

Cathode Current (µA)

Cathode Voltage (V)

-40 -20 0 20 40 60 80 100 120

2.40

2.42

2.44

2.46

2.48

2.50

2.52

2.54

2.56

2.58

Reference Voltage

vs Temperature

VZ =V

REF

IZ =10mA

Reference

Voltage (V)

Temperature (

°

C)

V

REF

=2.535V

V

REF

=2.495V

V

REF

=2.455V

AIC431/TL431A/TL431

6

n

TYPICAL PERFORMANCE CHARACTERISTICS (Continued )

-40

-20020406080100

120

0.70

0.75

0.80

0.85

0.90

0.95

1.00

1.05

1.10

1.15

1.20

Reference Input Current

vs Temperature

Reference

Input Current (

µ

A)

Temperature (

°

C)

R1=10K

Ω

R2=∞
IZ=10mA

-40 -20 0 20 40 60 80 100 120

0.00

0.04

0.08

0.12

0.16

0.20

0.24

0.28

VZ=V

REF

IZ=1mA to100mA
F <1KHz

Dynamic Impedance vs Temperature

Dynamic

Impedance (

Ω)Temperature (

°

C)

0510152025303540

-6-5-4-3-2-10

Change in Reference Voltage

vs Cathode Voltage

Change

in

Reference

Voltage (mV)

Cathode Voltage (V)

IZ =10mA

TA =25°C

-40

-20020406080100

120

0.0

0.5

1.0

1.5

2.0

2.5

Off-State Cathode Current vs Temperature

Off-State Cathode Current (µA)

Temperature (°C)

V

REF

=0V

VZ=30V

10

1001k10k

100k1M10M

-10

01020304050607080

Av

IZ =10mA
TA=25°C

Small Signal Voltage Amplification vs Frequency

Small Signal Voltage Amplification

Frequency (Hz)

R1
10K

R

250

+

V

IN

C

IN

47µF

V1

AIC431

Output

Test Circuit For Frequency Response

AIC431/TL431A/TL431

7

n

TYPICAL PERFORMANCE CHARACTERISTICS (Continued )

Pulse Response

Input

Output

RA

50

RB

220

AIC431

OUTPUT

Pulse

Generator

f=100kHz

Test Circuit For Pulse Respnose

1E-4 1E-3 0.01 0.1 1 10

0

20

40

60

80

100

Stability Boundary Conditions

Cathode Current (mA)

Load Capacitance (µF)

VZ=V

REF

Stable

Stable

C

L

VIN

R
150

AIC431

VZ

The areas between the curves represent condition that Test Circuit for Stability Boundary Conditions
may cause the device oscillate

1K10K100K1M

0.1110

Iz=10mA

TA=25°C

Dynamic impedance vs. Frequency

Dynamic

Impedance (

Ω)Frequency

(Hz)

R1

50

+

AC

3V

R2
50

AIC431

GND

Output

+

AIC431/TL431A/TL431

8

n

SYMBOL

n

BLOCK DIAGRAM

ANODE (A)

REF (R)

CATHODE (C)

AIC431

ANODE (A)

CATHODE (C)

REF (R)

+

-

2.495V

n

APPLICATION EXAMPLES

V

IN

R1A

R2A

R1B

R2B

AIC431

AIC431

R

ON

OFF

C

V

IN

+

AIC431

LED on when Low Limit<VIN< High Limit
Low Limit ≅ V

REF

(1+R1B/R2B) Delay=R x C x

ln (

V

V V

IN

IN REF−

)

High Limit ≅ V

REF

(1+R1A/R2A)

Fig. 4 Voltage Monitor Fig. 5 Delay Timer

R

CL

I

OUT

V

IN

AIC431

R

V

IN

S

I

OUT

AIC431

I

OUT=VREF

/ R

CL

I

OUT=VREF /RS

Fig. 6 Current Limiter or Current Source Fig. 7 Constant-Current Sink

AIC431/TL431A/TL431

9

n

APPLICATION EXAMPLES (Continued)

V

OUT

R1

R2

V

IN

AIC431

V

IN

R1

R2

V

OUT

FUSE

AIC431

V

OUT

≅ (1+R1/R2) x V

REF

V

LIMIT

≅ (1+R1/R2) x V

REF

Fig 8. Higher-Current Shunt Regulator Fig 9. Crow Bar

R1A

R2A

R2B

R1B

V

IN

Output ON when

Low Limit <V

IN

< High Limit

+

V

BE

AIC431

AIC431

Low Limit≅ V

REF

( 1+ R1B/ R2B )+ V

BE

High Limit ≅ V

REF

( 1+ R1A/ R2A )

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

AIC431/TL431A/TL431

10

n

PHYSICAL DIMENSIONS

l 8 LEAD PLASTIC SO (unit: mm)

SYMBOL MIN MAX

A 1.35 1.75

A1 0.10 0.25

B 0.33 0.51
C 0.19 0.25
D 4.80 5.00
E 3.80 4.00

e 1.27(TYP)

H 5.80 6.20

L 0.40 1.27

D

H

e

A

B

A1

C

E

L

l SOT-23 (unit: mm)

SYMBOL MIN MAX

A 1.00 1.30
A1 — 0.10
A2 0.70 0.90

b 0.35 0.50
C 0.10 0.25
D 2.70 3.10
E 1.40 1.80

e 1.90 (TYP)
H 2.60 3.00

L 0.37 —

H

A1

AA2b

θ

1

L

C

D

E

e

θ1

1° 9°

l SOT-23 MARKING

Part No. Marking Part No. Marking
AIC431CUN AC1N AIC431CUS AC1S
TL431CUN AC2N TL431CUS AC2S
TL431ACUN AC3N TL431ACUS AC3S

AIC431/TL431A/TL431

11

n

PHYSICAL DIMENSIONS (Continued)

l SOT-89 (unit: mm)

SYMBOL MIN MAX

A 1.40 1.60
B 0.36 0.48
C 0.35 0.44
D 4.40 4.60

D1 1.62 1.83

E 2.29 2.60

e 1.50 (TYP.)

e1 3.00 (TYP.)

H 3.94 4.25

B

e

H

e1

D

D1

A

C

L

E

L 0.89 1.20

l SOT-89 MARKING

Part No. Marking
AIC431CX AC01B
TL431CX AC02B
TL431ACX AC03B

l TO-92 (unit: mm)

SYMBOL MIN MAX

A 4.32 5.33
C 0.38 (TYP.)
D 4.40 5.20
E 3.17 4.20

e1 1.27 (TYP.)

A

L

e1

D

C

E

L 12.7 -