May25-07 RevH

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

© 2007 Sipex Corporation

Solved by

TM

Features

■

1A Output Current

■

1.4MHz Constant Frequency Operation

■

97% Efficiency Possible

■

0.5µA (Max.) Shutdown Current

■

Adjustable Output Voltage

■

No External FETs 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

■

Lead Free, RoHS Compliant package: l

Small (3mm X 3mm) 10 Pin DFN or MSOP

applications

■

Mobile Phones

■

PDAs

■

DSCs

■

MP3 Players

■

USB Devices

■

Point of Use Power

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

using one Li-Ion cell, with up to 1A of output current. The 1.4MHz switching frequency and

PWM control loop are optimized for a small value inductor and ceramic output capacitor,

for space constrained portable designs. 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. 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 140ºC over-temperature shutdown.

typical application circuit

Description

1A, High Efficiency, Fixed 1.4 MHz

Current Mode PWM Buck Regulator

3.3V at 1A

10

µF

100k

Ω

340k

Ω

4.7

µH

10

µF

10nF

4k

Ω

1

2

3

4

5

10

9

8

7

6

SP6652

FB

COMP

SD

LX

SYNC

MODE

ENABLE

SHUTDOWN

3.6V - 5.5V

10

Ω

1

µF

sp6652

SP6652

10 Pin DFN

10

9

8

7

6

1

2

3

4

5

P

GND

FB

COMP

SD

LX

P

VIN

S

VIN

SYNC

MODE