www.fairchildsemi.com

REV. 1.1.1 3/20/02

Features

• Low dropout voltage

• Load regulation: 0.05% typical

• On-chip thermal limiting

• SO-8 and 5-lead SPAK and TO-252 DPAK packages

• Fixed 3.3V, and adjustable or 2.5V or 1.8V fixed

• Stable with low ESR output capacitors

Applications

• Hard Disk Drives, CD-ROMs, DVDs

• High efficiency linear regulators

• Post regulators for switching supplies

• ADSL and Cable Modems

• 5V to 3.3V and 2.5V linear regulators

• Motherboard with multiple supplies

Description

The FAN1537 provides 2 output voltages: 3.3V, and either

adjustable or 2.5V or 1.8V fixed with 1.0A each output

current capability. These devices have been optimized for

low voltage where transient response and minimum input

voltage are critical.

Current limit features protect the outputs against short circuit

currents. On-chip thermal limiting provides protection

against any combination of overload and ambient tempera-

ture that would create excessive junction temperatures.

The FAN1537 series regulators are available in SO-8 and

5-lead SPAK and TO-252 DPAK power packages.

Typical Applications

22

µF

2.5V at 1.0A

3.3V at 1.0A

22

µF

+

+

V1

NC GND

V2

FAN1537A

22

µF

+

22

µF

2.5V at 1.0A

3.3V at 1.0A

+

22

µF

+

22

µF

3.3V at 1.0A

22

µF

+

+

V1

GND

FB

V2

FAN1537B

22

µF

+

22

µF

R1

54.9

Ω

R2

124

Ω

1.8V at 1.0A

3.3V at 1.0A

+

22

µF

+

FAN1537

Dual 1A Adjustable/Fixed Low Dropout

Linear Regulators