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SC412A

POWER MANAGEMENT

Pin #

Pin Name

Pin Function

1

LX

Switching (phase) node

2

BST

Boost capacitor connection for high-side gate drive

3

VCC

5V power input for internal analog circuits and gate drive outputs

4

DL

Gate drive output for the low-side external MOSFET

5

GND

Power ground — the return point for the DL driver output and the reference point

for the ILIM and Zero Cross circuits

6

RTN

Return or analog ground for VOUT sense — connect to GND at the chip

7

NC

Not connected internally — leave unconnected or connect to GND

8

NC

Not connected internally — leave unconnected or connect to GND

9FB

Feedback input — connect to an external resistor divider from

VOUT to program the output voltage

10

VOUT

Output voltage sense point for determining the on-time

11

PGOOD

Open-drain Power Good indicator — high impedance indicates power is good —

an external pull-up resistor is required.

12

EN

Enable input — connect EN to RTN to disable the SC412A

13

ILIM

Current limit sense point — to program the current limit connect a resistor from ILIM to

LX or to a current sense resistor

14

NC

Not connected internally — leave unconnected or connect to GND

15

NC

Not connected internally — leave unconnected or connect to GND

16

DH

Gate drive output for the high-side external FET

TPAD

Thermal pad for heatsinking purposes — not connected internally — connect to system

ground through preferably one large via or multiple smaller vias

Pin Descriptions