1

Date:5/25/04

SP6652 1A, High Efficiency, High Frequency Current Mode PWM Buck Regulator

© Copyright 2004 Sipex Corporation

SP6652

FEATURES

■ 1A Output Current

■ 1.2MHz Constant Frequency Operation

■ 97% Efficiency Possible

■ Pin Selectable Forced PWM or PWM/PFM Modes

■ Ultra Low Quiecent Current in PFM Mode: 50µA

■ 500nA (Max.) Shutdown Current

■ Output Adjustable Down to 0.75V

■ No External FET's or Schottky Diode Required

■ Uses Small Value Inductors and Ceramic

Output Capacitors

■ Low Dropout Operation: 100% Duty Cycle

■ Soft Start and Thermal Shutdown Protection

■ Easy Frequency Synchonization

■ Small 10 Pin MSOP and 10 Pin DFN Package

APPLICATIONS

■ Mobile Phones

■ PDA's

■ DSC's

■ MP3 Players

■ USB Devices

■ Point of Use Power

The SP6652 is high efficiency, synchronous buck regulator ideal for portable applications using

one Li-Ion cell, with up to 1A output current. The 1.2MHz switching frequency and PWM control

loop are optimized for small value inductor and ceramic output capacitor, for space constrained

portable designs. At light load, the SP6652 can operate in either PFM mode for high efficiency,

or PWM mode for constant frequency. In addition, the input voltage range of 2.7V to 5.5V;

excellent transient response, output accuracy, and ability to transition into 100% duty cycle

operation, further extending useful battery life, make the SP6652 a superior choice for a wide

range of portable power applications. The output voltage is externally programmable down to

0.75V. A logic level shutdown control, external clock synchronization, and forced-PWM or

automatic control inputs are provided. Other features include soft-start, over current protection

and 140(C over-temperature shutdown.

®

3.3V at 1A

10µF

100k

340k

4.7µF

10µF

6.2nF

8k

1

2

3

4

5

10

9

8

7

6

SP6652

FB

COMP

SD

LX

SYNC

MODE

ENABLE

SHUTDOWN

TYPICAL APPLICATION SCHEMATIC

DESCRIPTION

SP6652

10 Pin MSOP

10

9

8

7

6

LX

SYNC

MODE

FB

COMP

SD

1

2

3

4

5

1A, High Efficiency, High Frequency Current Mode PWM

Buck Regulator

Now Available in Lead Free Packaging