Preliminary

RT9263

DS9263-00 November 2001

www.richtek-ic.com.tw

1

High Efficiency, Low Supply Current,

Step-up DC/DC Converter

General Description

The RT9263 is a compact, high efficient, step-up

DC/DC converter with an adaptive current mode

PWM control loop, providing a stable and high

efficient operation over a wide range of load

currents. It operates in both continuous and

discontinuous current modes in stable waveforms

without external compensation.

The low start-up input voltage below 1V makes

RT9263 suitable for 1 to 4 battery cell applications

providing up to 400mA output current. The 550KHz

high switching rate minimized the size of external

components. Besides, the 17

µA low quiescent

current together with high efficiency maintains long

battery lifetime.

Ordering Information

RT9263

Typical Application Circuit

Features

1.0V Low Start-up Input Voltage

High Supply Capability to Deliver 3.3V 100mA

with 1V Input Voltage

17

µµµµA Quiescent (Switch-off) Supply Current

90% Efficiency

550KHz Fixed Switching Rate

Providing Flexibility for Using Internal and

External Power Switches

SOT89-5 Package

Applications

PDA

Portable Instrument

DSC

Pin Configurations

Part Number

Pin Configurations

RT9263CCX5

(Plastic SOT89-5)

TOP VIEW

1. CE

2. VDD

3. FB

4. LX

5. GND

RT9263ECX5

(Plastic SOT89-5)

TOP VIEW

1. EXT

2. VDD

3. FB

4. LX

5. GND

Fig. 1 RT9263CCX5 Typical Application for Portable Instruments below 400mA

Operating temperature range

C: Commercial standard

Package type

X5 : SOT89-5

C : Chip enable control

E : Driver for external power devices

54

3

2

1

54

3

2

1

C1

100

µF

VDD

CE

LX

GND

FB

3.3V

C2

1

µF

D1

1N5819

L1

4.7

µH

R1

1.6M

R2

980K

100pF

100

µF

RT9263CCX5

+