Connection Diagram

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20127003

MXA14A

ETSSOP-14

Pin Descriptions

AVIN (Pin 1): Chip bias input pin. This provides power to the

logic of the chip. Connect to the input voltage or a separate

rail.

EN (Pin 2): Enable. Connect this pin to ground to disable the

chip; connect to AVIN or leave floating to enable the chip;

enable is internally pulled up.

SGND (Pin 3): Signal ground.

SS (Pin 4): Soft-start pin. Connect this pin to a small capaci-

tor to control startup. The soft-start capacitance range is

restricted to values 1 nF to 50 nF.

NC (Pins 5, 12 and 13): No connect. These pins must be

tied to ground or left floating in the application.

PVIN (Pins 6, 7): Input supply pin. PVIN is connected to the

input voltage. This rail connects to the source of the internal

power PFET.

SW (Pins 8, 9): Switch pin. Connect to the output inductor.

PGND (Pins 10, 11): Power ground. Connect this to an

internal ground plane or other large ground plane.

SNS (Pin 14): Output voltage sense pin. Connect this pin to

the output voltage as close to the load as possible.

Exposed Pad: Connect to ground.

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