5

SC220Q

Pin Descriptions

Pin # Pin Name Pin Function



SW

Switching output node — connect to the output LC filter.

2

PVIN

Power input supply voltage (2.7 to 5.5V).

3

VOUT

Input for sensing the output of LC filter.

4

FB

Input for regulation of output LC filter — Using R

to the typical application circuit diagram on page ).

5

EN

Enable Input — when low, circuit draws <µA. Apply a square wave clock at EN to synchronize the switching frequency

with an external clock. It is recommended that the externally applied clock frequency should not be above 20MHz.

6

AVIN

Input supply voltage

7

AGND

Analog ground

8

PGND

Power ground

Block Diagram

S W

P GN D

E N

A V IN

P V IN

FB

6

A GN D

8

4

1

7

3

2

5

V OU T

C LIM

C om pensator

C ontrol Logic

ZC D

+

-

1 .0 V

+

-

Frequency

C ontrol

S oft-S tart

Therm al

S hutdow n

R E F

1.0V

OS C

20 M H z

D river

E xternal Freq .

S ynchronization

C om p

E rror

A m p