© 2007 Fairchild Semiconductor Corporation

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FSFR2100 • 1.0.0

3

Pin Assignments

1

2

3 4 5 6 7 8

9

10

V

DL

CON

R

T

CS

SG

PG

LVcc

HVcc

V

CTR

Figure 3. Package Diagram

Pin Definitions

Pin #

Name

Description

1

This pin is the drain of the high-side MOSFET. It is typically connected to the input

DC link voltage.

2

CON

This pin is for enable/disable and protection. When the voltage of this pin is above

0.6V, the IC operation is enabled. When the voltage of this pin drops below 0.4V,

gate drive signals for both MOSFETs are disabled. When the voltage of this pin

increases above 5V, protection is triggered.

3

This pin programs the switching frequency. Typically, an opto-coupler is connected

to control the switching frequency for the output voltage regulation.

4

CS

This pin senses the current flowing through the low-side MOSFET. Typically,

negative voltage is applied on this pin.

5

SG

This pin is the control ground.

6

PG

This pin is the power ground. This pin is connected to the source of the low-side

MOSFET.

7

LVcc

This pin is the supply voltage of the control IC.

8

NC

No connection.

9

HVcc

This pin is the supply voltage of the high-side drive circuit IC.

10

This pin is the drain of the low-side MOSFET. Typically, a transformer is connected

to this pin.