www.fairchildsemi.com

REV. 1.0.2 8/26/03

Features

• 70dB Ripple rejection ( >45dB up to 1MHz)

• 150µsec Power On Time

• 150µsec Enable Time

•Low noise - 50µVrms

• Enable optimized for CDMA time slices

• 180 mV dropout voltage at 150 mA

• Enable/Shutdown Control

• Enable time independent of noise bypass capacitor value

•SOT23-5 package

• Thermal limiting

• 300 mA trimmed current limit

Applications

• Cellular Phones and accessories

•PDAs

• Portable cameras and video recorders

• Laptop, notebook and palmtop computers

Description

The FAN2534/FAN2535 family of micropower low-dropout

voltage regulators utilize CMOS technology to offer a new

level of cost-effective performance in GSM, TDMA, and

CDMA cellular handsets, laptop and notebook computers,

and other portable devices. Proprietary design technics

ensure high ripple rejection. Other features include low

noise, short circuit current limit, thermal shutdown circuit,

low dropout voltage, fast enable required in CDMA handset

applications, exceptional loop stability to accommodate a

wide variety of external capacitors, and a compact SOT23-5

surface-mount package. These products offer significant

improvements over older Bipolar and CMOS designs and are

pin-compatible with many popular devices.

The FAN2534 and FAN2535 devices are distinguished by

the assignment of pin 4:

FAN2534: pin 4 – ADJ, allowing the user to adjust the

output voltage over a wide range using an external voltage

divider.

FAN2534-XX: pin 4 – BYP, to which a bypass capacitor

may be connected for optimal noise performance. Output

voltage is fixed, as specified by the suffix XX.

FAN2535-XX: pin 4 – ERR, a flag which indicates that the

output voltage has dropped below the specified minimum

due to a fault condition.

The standard fixed output voltages available are 2.6V, 2.85V,

and 3.0V . Custom output voltages are also available: please

contact your local Fairchild Sales Office for information.

FAN2534/FAN2535

150 mA CMOS LDO Regulator with Fast Start, Enable

Block Diagrams

FAN2534

EN

ADJ

GND

Thermal

Sense

p

VIN

VOUT

Bandgap

Error

Amplifier

FAN2534-XX

EN

BYP

GND

GND

Bandgap

Thermal

Sense

p

Error

Amplifier

VIN

VOUT

FAN2535-XX

EN

ERR

Bandgap

Thermal

Sense

p

Error

Amplifier

VIN

VOUT