ASTEC AS431CR5ST, AS431CR5SB, AS431CR5SA, AS431CR5S7, AS431CR5S13 Datasheet

SEMICONDUCTOR

AS431

Precision Adjustable Shunt Reference

Features

¥Temperature-compensated: 30 ppm/¡C

¥Trimmed bandgap reference

¥Internal amplifier with 150 mA capability

¥Multiple temperature ranges

¥Low frequency dynamic output impedance: < 150 m½

¥Low output noise

¥Robust ESD protection

Description

The AS431 is a three-terminal adjustable shunt regulator providing a highly accurate bandgap reference. The adjustable shunt regulator is ideal for a wide variety of linear applications that can be implemented using external components to obtain adjustable currents and voltages.

In the standard shunt configuration, the combination of low temperature coefficient (TC), sharp turn-on characteristics, low output impedance and programmable output voltage make this precision reference a perfect zener diode replacement.

The AS431 precision adjustable shunt reference is offered in four bandgap tolerances: ±0.25%, ±0.5%, ±1.0%, and ±2.0%.

Pin Configuration Ñ Top view

TO-92 (LP)

SOIC (D)

CATHODE	1	8	REFERENCE
CATHODE
ANODE	2	7	ANODE
ANODE			ANODE
ANODE	3	6
REFERENCE			N/C
N/C	4	5

	SOT-23/5L (DBV)
N/C	ANODE
N/C
CATHODE	REFERENCE

Ordering Information

AS431 A 2 D 7

SOT-89 (S)

CATHODE

ANODE

REFERENCE

Circuit Type:

Packaging Option:

Precision Adjustable

A

= Ammo Pack

Shunt Regulator

B

= Bulk

T

= Tube

Temperature Range:

7 = Tape and Reel (7" Reel Dia)

A = 0°C to 70°C

13 = Tape and Reel (13" Reel Dia)

B = 0°C to 105°C

Package Style:

C = –40°C to +85°C

D

= SOIC

Bandgap Tolerance:

DBV = SOT-23/5L

2

= ±2%

LP

= TO-92

1

= ±1%

S

= SOT-89

R5

= ±0.5%

R25 = ±0.25%

ASTEC Semiconductor

1

AS431

Precision Adjustable Shunt Reference

Functional Block Diagram

CATHODE (K)

REFERENCE	+
(R)
	Ð
	2.5 V

ANODE (A)

Absolute Maximum Ratings

Parameter	Symbol	Rating	Units
Cathode-Anode Reverse Breakdown	VKA	37	V
Anode-Cathode Forward Current	IAK	1	A
Operating Cathode Current	IKA	250	mA
Reference Input Current	IREF	10	mA
Continuous Power at 25¡C	PD
TO-92		775	mW
8L SOIC		750	mW
SOT-89		1000	mW
SOT-23/5L		200	mW
Junction Temperature	TJ	150	¡C
Storage Temperature	TSTG	Ð65 to 150	¡C
Lead Temperature, Soldering 10 Seconds	TL	300	¡C

Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.

Recommended Conditions

Parameter	Symbol	Rating	Unit
Cathode Voltage	VKA	VREF to 20	V
Cathode Current	IK	10	mA

Typical Thermal Resistances

Package	θJA	θJC	Typical Derating
TO-92	160¡C/W	80¡C/W	6.3 mW/¡C
SOIC	175¡C/W	45¡C/W	5.7 mW/¡C
SOT-89	110¡C/W	8¡C/W	9.1 mW/¡C
SOT-23/5L	575¡C/W	150¡C/W	1.7 mW/¡C

ASTEC Semiconductor

2

Precision Adjustable Shunt Reference

AS431

Electrical Characteristics

Electrical Characteristics are guaranteed over full junction temperature range (0 to 105¡C). Ambient temperature must be derated based on power dissipation and package thermal characteristics. The conditions are: VKA = VREF and IK = 10 mA unless otherwise stated.

					Test	AS431 (0.25%)			AS431 (0.5%)				Test
	Parameter	Symbol			Condition	Min.	Typ.	Max.	Min.	Typ.	Max.	Unit	Circuit
	Reference Voltage		VREF		TA = 25¡C	2.496	2.503	2.509	2.490	2.503	2.515	V	1
					Over temp.	2.475		2.530	2.469		2.536	V	1
	ÆVREF with Temp*		TC				0.07	0.20		0.07	0.20	mV/¡C	1
	Ratio of Change in		ÆVREF		VREF to 10 V	Ð2.7	Ð1.0		Ð2.7	Ð1.0
	VREF to Cathode		ÆVK									mV/V	2
					10 V to 36 V	Ð2.0	Ð0.4	0.3	Ð2.0	Ð0.4	0.3
	Voltage
	Reference Input		IREF				0.7	4		0.7	4	µA	2
	Current
	IREF Temp Deviation		ÆIREF		Over temp.		0.4	1.2		0.4	1.2	µA	2
	Min IK for Regulation		IK(min)				0.4	1		0.4	1	mA	1
	Off State Leakage		IK(off)		VREF = 0 V,		0.04	250		0.04	250	nA	3
					VKA = 36 V
	Dynamic Output		ZKA		f ² 1 kHz		0.15	0.5		0.15	0.5	½	1
	Impedance				IK = 1 to 150 mA

					Test	AS431 (1.0%)			AS431 (2.0%)				Test
	Parameter	Symbol			Condition	Min.	Typ.	Max.	Min.	Typ.	Max.	Unit	Circuit
	Reference Voltage		VREF		TA = 25¡C	2.470	2.495	2.520	2.440	2.490	2.550	V	1
					Over temp.	2.449		2.541	2.430		2.569	V	1
	ÆVREF with Temp*		TC				0.07	0.20		0.07	0.20	mV/¡C	1
	Ratio of Change in		ÆVREF		VREF to 10 V	Ð2.7	Ð1.0		Ð2.7	Ð1.0
	VREF to Cathode		ÆVK									mV/V	2
					10 V to 36 V	Ð2.0	Ð0.4	0.3	Ð2.0	Ð0.4	0.3
	Voltage
	Reference Input		IREF				0.7	4		0.7	4	µA	2
	Current
	IREF Temp Deviation		ÆIREF		Over temp.		0.4	1.2		0.4	1.2	µA	2
	Min IK for Regulation		IK(min)				0.4	1		0.4	1	mA	1
	Off State Leakage		IK(off)		VREF = 0 V,		0.04	250		0.04	250	nA	3
					VKA = 36 V
	Dynamic Output		ZKA		f ² 1 kHz		0.15	0.5		0.15	0.5	½	1
	Impedance				IK = 1 to 150 mA

*Calculating Average Temperature Coefficient (TC). Refer to following page.

ASTEC Semiconductor

3