ZXSC100

SEMICO NDUC TORS

ISSUE 3 - JANUARY 2004

6

Pin

No.

Name

Description

1

EM

Emitter of internal drive transistor. Connect to RE in lower power applications. Must be

unconnected in higher power applications

2

BAS

Not connected in lower power applications. Connect to base of external drive transistor

in higher power applications

3

RE

external sense resistor. Connect emitter of external drive transistor in higher power

applications

Supply voltage, generally NiMH, NiCd single cell

Inductor current sense input. Internal threshold voltage set to 25mV. Connect external

sense resistor

6

FB

Feedback sense. Internal threshold set to 730mV. Connect external resistive divider to

output voltage

Ground

PIN DESCRIPTIONS

RE

EM

BAS

VDRIVE

VCC

ISENSE

FB

GND

5

6

7

8

4

3

2

1

REFERENCE DESIGNS

Three typical DC-DC step-up converter applications

for the ZXSC300 are shown. Firstly with a maximum

output power of 0.33W, secondly with a maximum

output power of 1.0W and finally driving white LED’s in

a flashlight application.

Low power solution (330mW) efficiency