Rev. 10/2/00

AS1582

3A Ultra Low Dropout Voltage Regulator

Fast Response, Adjustable & Fixed

FEATURES

APPLICATIONS

• Low Dropout Voltage 500mV at 3A Full Load Current

• 3.3V to 2.8V ATX Power Supplies

• Fixed Output Voltages of 3.3V, 2.8V & 2.5V

• 3.3V to 2.9V for Portable PENTIUM





 Processor

• Adjustable Output Down to 1.2V from ATX Power Supply

• 5V to 3.5V VRE Supply

• Extremely Tight Voltage and Line Regulation

• High Efficiency “Green” Computer Systems

• Standard 5-Terminal Low Cost TO-220 & TO-263

PRODUCT DESCRIPTION

The AS1582 is a 3A Low Dropout Regulator with extremely low dropout voltage. The adjustable version requires only two external

resistors to set the output voltage. The fixed version has a preset output of 3.3V, 2.8V or 2.5V and does not require any external

resistors. The AS1582 features a low dropout of less than 400mV(typ.) and offers fast transient response. This device is suitable for

Pentium applications requiring 2.8V or 2.5V from 3.3V ATX power supplies, where a low current input voltage 1V greater than

the output voltage is needed. With an external sense pin the load regulation is less than 1mV. This device is an excellent choice for

the use in powering low voltage microprocessors that require a lower dropout, fast transient response to regulate from 3.3V and 5V

supplies. The AS1582 is also an excellent choice as a post regulator for switching supplies applications.

The AS1582 offers full protection against over-current faults, reversed input polarity, over temperature operation and positive and

negative transient voltage.

The AS1582 is offered in a 5 pin TO-220 and TO-263 compatible with industry standard 5-terminal regulators. For 7A, 5A and 1.5A

ultra low dropout versions refer to AS1580, AS1581 and AS1583 data sheets respectively.

ORDERING INFORMATION

TO-22O

5-PIN

TO-263

5-PIN

OUTPUT

AS1582U

AS1582T

Adjustable

AS1582U-X

AS1582T-X

Fixed

Consult with factory for other fixed output voltages.

X= Output Voltage (3.3V, 2.8V or 2.5V)

PIN CONNECTIONS

TO-263-5 (T)

Top View

45

AS1582

12 3

1. SENSE

2. ADJ or FIXED

3. V

OUT

4. V

CTRL

5. V

IN

TO-220-5 (U)

Front View

5

4

3

2

1

AS1582

1. SENSE

2. ADJ or FIXED

3. V

OUT

4. V

CTRL

5. V

IN