1

Jun 17-06 Rev F

SPX1582 3A Ultra Low Dropout Voltage Regulator

© 2006 Sipex Corporation

SPX1582

DESCRIPTION

FEATURES

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

■ Adjustable Ouput Down to 1.25V from ATX Power Supply

■ Fixed Output Voltages of 3.3V and 2.5V

■ Extremely Tight Load and Line Regulation

■ Standard 5-Terminal Low Cost TO-220 and TO-263

The SPX1582 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 SPX1582 features a low dropout of 400mV(Typ.) and offers fast transient

response. This device is suitable for Pentium applications requiring 2.8V, 2.5V from 3.3V ATX power supplies, where

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 SPX1582 is also an excellent choice

as a post regulator for switching supply applications.

The SPX1582 offers protection against over-current faults, reversed input polarity, over temperature operation and

positive or negative transient voltages.

The SPX1582 is offered in a 5 pin TO-220 and TO-263 compatible with industry standard 5-terminal regulators. For

5A, 3A and 1.5A ultra low dropout versions refer to SPX1581, SPX1582 and SPX1583 data sheets respectively.

3A Ultra Low Dropout Voltage Regulator

Fast Response, Adjustable & Fixed

APPLICATIONS

■ 3.3V to 2.8V ATX Power Supplies

■ 5V to 3.5V VRE Supply

■ High efficiency "Green" Computer Systems

3

2

1

SPX1582

5 Pin TO-220

4 5

C4

2x330μF

2.5V

R1

124Ω

R2

124Ω

SENSE

C2

10μF

C1

330μF

3.3V

5V

SPX1582

5

4

2

3

1

ADJ

C3

.033μF

C4

2x330μF

2.5V

SENSE

C2

10μF

C1

330μF

3.3V

5V

SPX1582

5

4

2

3

1

GND

Typical Fixed Regulator

Adjustable Regulator

TYPICAL APPLICATIONS CIRCUIT

Now Available in Lead Free Packaging

1

3

2

5

4

SPX1582

5 Pin TO-263