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SC251

POWER MANAGEMENT

Pin#

Pin Name

Pin Function

1

VIN

Input supply pin.

2

VREF

A 2.85V LDO reference voltage supply - 10mA max load that can be used as a supply

for power amplifier bias inputs.

3GD

A push pull external PFET Gate drive control output - connect to the gate of an external

MOSFET to control a low resistance path between V

drop is needed (optional - if not used leave floating). A low state turns on the MOSFET.

4

EN

Enable pin - controls both the switching converter and the VREF output. Active high.

5

VMODE

Input control to select the V

6

VDAC

Analog control voltage input - ranges between 0.3 and 1.2V for exponential control of

V

V

optional low R

7

GND

System and logic ground.

8

VOUT

Output voltage pin.

9

PGND

Ground reference for internal N-channel MOSFET.

10

LX

Switch node connection to inductor. This pin connects to the drains of the internal

main and synchronous power MOSFET switches.

T

Thermal Pad

Pad for heatsinking purposes. Connect to ground plane using multiple vias.

Not connected internally.

Pin Description