1

Date: 5/25/04

SP6650 High Efficiency 600mA Synchronous Buck Regulator

© Copyright 2004 Sipex Corporation

High Efficiency 600mA Synchronous Buck Regulator

Ideal for portable designs powered with Li Ion battery

SP6650

FEATURES

■ 95% High Efficiency

■ Proprietary Control Loop

■ 2.7V to 6.5V Input Voltage Range

■ 3.3V or Adjustable Output Voltage

Range

■ 2% Output Voltage Accuracy

■ 600mA Output Current

■ 100% Duty Cycle Operation

■ Programmable Inductor Peak Current

Limit (0.95A or 0.5A)

■ No External FET's Required

■ 3V Battery Low Indicator

■ 2.7V Undervoltage Lockout

■ Shutdown Control

■ Small 10-Pin MSOP

The SP6650 is ideal for portable applications that use a Li-Ion or 3 to 4 cell alkaline/NiCd/NiMH

input. The SP6650 extends battery life with it’s unique control loop scheme (patent pending),

which maintains high efficiency levels (> than 90%) over a wide range of output currents. Features

such as Inductor peak current control, protects the power supply from overload or short circuit

conditions, controls the startup current to prevent output overshoot and excessive battery drop,

and gives the user more flexibility in choosing an appropriate coil to optimize solution cost, size

and performance. Other features include a dedicated pin for manual shutdown, a battery low

indicator, and thermal protection.

TYPICAL APPLICATIONS CIRCUIT

®

RB

100kΩ

2.7-6.5 VDC

3.3V or 1.25V

to 5.0V

SP6650

10

9

8

7

6

1

2

3

4

5

R1

10Ω

C1

1µF

C2

47µF

L1 22µH

C3

47µF

R2

164k

R3

100k

C4

470pF

BLON

SHDN

LX

PGND

GND

FB

®

®

R4

100kΩ

DESCRIPTION

APPLICATIONS

■ PDA

■ CD Player

■ ADSL Modem

■ Digital Still Camera

Now Available in Lead Free Packaging

BLON

SHDN

SP6650

10 Pin MSOP

1

2

3

4

5

10

9

8

7

6

LX

PGND

GND

FB