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EZ1580/EZ1581

EZ1582/EZ1583

Dual Input Low Dropout Regulator

POWER MANAGEMENT

June 23, 2010

The EZ158X family of high performance positive voltage

regulators are designed for use in applications requiring

very low dropout voltage at up to 7, 5, 3 and 1.5 amps.

Capable of supplying up to 2.8V on boards where both

5V and 3.3V supplies are available, the superior dropout

characteristics of the EZ158X result in reduced heat

dissipation compared to regular LDOs. This allows for

heatsink size reduction or elimination. Additionally, the

EZ158X provides excellent regulation over variations in

line, load and temperature. Remote sense operation

allows compensating for trace, connector and other

resistive losses.

Outstanding features include very low dropout

performance at rated current, fast transient response,

remote sense, internal current limiting, thermal shutdown

and safe operating area protection of the output device.

The EZ158X is a five terminal adjustable or fixed 2.5V

voltage regulator available in the popular 5 pin TO-220

and TO-263 plastic packages.

540mV dropout @ 7A in dual supply mode

(EZ1580)

Remote sense operation

Fast transient response

0.5% initial accuracy

Line regulation typically 0.08%

Load regulation typically 0.08%

5 Pin TO-220 and TO-263 packages

Microprocessor supplies

Split plane microprocessor supplies

Advanced graphics cards

Sound cards

Low voltage logic supplies

Switching power supply post regulation

Notes:

(1) Capacitor values are for reference only. Good quality, low ESR tantalum or aluminum electrolytic capacitors

should be used. Increasing the value of the output capacitor will improve the overall transient response.

(2) If the same voltage is input to both PWR and CTL, then the dropout voltage will become 1.3V maximum.

(3) A small (~0.033µF) capacitor can be used to bypass the ADJ pin to improve transient response, if needed.

2.5V OUT

3.3V POWER IN

5V CONTROL IN

GROUND

GROUND

C2

10uF

C1

33uF

C3

68uF

R1

124

R2

124

U1

EZ158XCX

4

3

2

1

5

CTL

OUT

ADJ

SNS

PWR

VREF

2

R

I

1

R

2

R

1

V

V

ADJ

REF

OUT

•

+











 +

=

GROUND

GROUND

3.3V POWER IN

2.5V OUT

5V CONTROL IN

C2

10uF

U1

EZ158XCX-2.5

4

3

2

1

5

CTL

OUT

GND

SNS

PWR

C3

68uF

C1

33uF

Fixed Output Parts

Description

Features

Applications

Typical Application Circuits