Pin Descriptions 5-Pin SOT23

Pin

Name

Function

1

SW

Output switch. Connect to the inductor and catch diode.

2

GND

Signal and power ground pin. Place the bottom resistor of the feedback network as close as

possible to this pin.

3

FB

Feedback pin. Connect to external resistor divider to set output voltage.

4

EN

Enable control input. Logic high enables operation. Do not allow this pin to float or be

greater than VIN + 0.3V.

5

VIN

Input supply voltage.

Pin Descriptions 6-Pin LLP

Pin

Name

Function

1

FB

Feedback pin. Connect to external resistor divider to set output voltage.

2

GND

Signal and power ground pin. Place the bottom resistor of the feedback network as

close as possible to this pin.

3

SW

Output switch. Connect to the inductor and catch diode.

4

VIND

Power Input supply.

5

VINA

Control circuitry supply voltage. Connect VINA to VIND on PC board.

6

EN

Enable control input. Logic high enables operation. Do not allow this pin to float or be

greater than VINA + 0.3V.

DAP

Die Attach Pad

Connect to system ground for low thermal impedance, but it cannot be used as a

primary GND connection.

www.national.com

3