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POWER MANAGEMENT

SC613

Low Noise Regulated Charge

Pump with Selectable Output

February 8, 2005

Description

Features

Applications

Typical Application Circuit

The SC613 is a versatile charge pump designed for use in battery

operated power supply applications. The wide input range is

matched for Li-Ion battery applications. Only two 1uF ceramic

bucket capacitors are required, and the inductorless implementa-

tion provides a reduced-EMI solution. Low noise mode switching

circuitry and constant output current allow the use of 1uF input

and output capacitors.

The SC613 charge pump regulator can be used for applications

that require up to 140mA of output current with a 4.5V output.

The 5.0V output version provides up to 100mA of output current.

The small package size, low component count and lower overall

system cost coupled with its low noise make the SC613 a supe-

rior solution compared to switch mode regulator designs.

Small size - MLP Micro 10 lead 3x3mm package

Selectable 5.0V or 4.5V output voltage

140mA available with 4.5V output

100mA available with 5.0V output

Short circuit protection

Soft Start function

Shutdown current <2µA

Selectable fixed frequencies of 262kHz and 650kHz

Low ripple

Regulated to +/-5%

Ease of use

Cellular phones

LED photo flash for cellular phones

LED backlighting

PDA power supplies

Portable electronics

Electronic books

Wireless web appliances

Cin

1.0uF

2.7V to 6.5V

Cbucket1

1.0uF

Cbucket2

1.0uF

VIN

EN

VSEL

FSEL

GND

CF2-

CF2+

CF1-

CF1+

VOUT

3

6

4

5

8

7

10

9

2

1

U1

Cout

1.0uF

UP TO 10 LEDS

4.5V or 5.0V