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Date: 09/27/05

SP6655 High Efficiency 400mA Synchronous Buck Regulator

© Copyright 2004 Sipex Corporation

SP6655

High Efficiency 400mA Synchronous Buck Regulator

The SP6655 is a 400mA synchronous buck regulator which is ideal for portable applications that

use a Li-Ion or 3 cell alkaline/NiCD/NiMH input. The SP6655’s proprietary control loop, 20µA light

load quiescent current, and 0.3Ω power switches provide excellent efficiency across a wide range

of output currents. As the input battery supply decreases towards the output voltage, the SP6655

seamlessly transitions into 100% duty ratio operation, further extending useful battery life. The

SP6655 is protected against overload and short circuit conditions with a precise inductor peak

current limit. Other features include programmable under voltage lockout and low battery

detection, externally programmed output voltage down to 1.0V, logic level shutdown control, and

140°C over temperature shutdown.

®

Ideal for portable designs powered with Li Ion battery

DESCRIPTION

FEATURES

■ 98% Efficiency Possible

■ Small 10-Pin DFN Package

■ Ultra-low 20µA Quiescent Current

■ 625mA Inductor Peak Current Limit

■ Guaranteed Minimum 400mA Output

Current

■ 2.7V to 5.5V Input Voltage Range

■ Output Adjustable Down to 1.0V

■ 100% Duty Ratio Low Dropout

Operation

■ 80µA Light Load Quiescent Current in

Dropout

APPLICATIONS

■ Cell Phones

■ PDA's

■ DSC's

■ MP3 Players

■ USB Devices

■ Point of Use Power

TYPICAL APPLICATION SCHEMATIC

SP6655

10 Pin DFN

10

9

8

7

6

1

2

3

4

5

VIN

BLON

D1

D0

LX

P

GND

GND

V

OUT

FB

Now Available in Lead Free Packaging

BLON

VI

VO

D1

D0

10µF

L1

10µH

400mA

2.7V to 5.5V Input

10Ω

1µF

SP6655

BLON

D1

D0

LX

GND

FB

10µF

CF

22pF

200K

1M