1

Rev:A Date: 11/20/03

SP6681 High Efficiency Boost Charge Pump Regulator

© Copyright 2002 Sipex Corporation

High Efficiency Boost Charge Pump Regulator

SP6681

FEATURES

■ Ideal for Li Ion or 3V to 5V Conversion

■ Low Profile, Inductorless Regulator

■ Up To 96% Power Efficiency

■ +2.7V to +5.5V Input Voltage Range

■ 5.0V, 50mA Output, 4% Accuracy

■ Low EMI Design

■ Low Quiescent Current: 175µA

■ Low Shutdown Current: 4µA

■ Optional External Clock: 32.768kHz

■ Thermal Shutdown Protection

■ Programmable Frequencies:

8.192kHz, 32.768kHz, or 262.14kHz

■ Internal Oscillator: 16kHz or 130kHz,

when CLK Pin Is Held High

■ Ultra small 10-Pin MSOP Package

DESCRIPTION

The SP6681 is a charge pump ideal for converting a +3.6V Li-Ion battery input to a +5.0V

regulated output. An input voltage range of +2.7V to +5.5V is converted to a regulated output

of 5.0V. The SP6681 device will operate at three different switching frequencies correspond-

ing to three different output resistances and load current ranges. An external 32.768kHz

nominal clock signal is used to produce three synchronized pump frequencies through the use

an internal phase lock loop to drive the charge pump. Two control inputs can adjust the internal

pump frequency on the fly to 8.192kHz (f

x 8). The charge pump configuration dynamically changes to optimize power efficiency. At

low input voltages the charge pump doubles the input while at higher inputs the output is 1.5

times the input. The SP6681 can deliver high power efficiencies up to 96% with low quiescent

currents from 175µA to 800µA. The SP6681 is offered in a 10-Pin µSOIC package.

®

V

OUT

C/4

Cx8

CLK

GND

SP6681

8

CF1P

CF1N

CF2P

CF2N

4.7µF

2.2µF

2

9

10

7

1

6

45

3

+3.6V

Lithium-Ion

Battery

+5.0V output

V

IN

2.2µF

2.2µF

*All Capacitors Are Ceramic

APPLICATIONS

■ GSM SIM Card Power Supplies

■ 3V to 5V Boost Applications

■ Li Ion to 5.0V Boost Applications

■ White LED Driver

■ Smart Card Readers