MP2372 – 3A, 28V, 925KHZ STEP-DOWN CONVERTER

MP2372 Rev. 0.92

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4

12/22/2009

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PIN FUNCTIONS

Pin #

Name Description

1

BS

High-Side Gate Drive Boost Input. BS supplies the drive for the high-side N-Channel MOSFET

switch. Connect a 10nF or greater capacitor from SW to BS to power the high side switch.

2

IN

Power Input. IN supplies the power to the IC, as well as the step-down converter switches.

Drive IN with a 4.5V to 28V power source. Bypass IN to GND with a suitably large capacitor to

eliminate noise on the input to the IC. See Input Capacitor

3

SW

Power Switching Output. SW is the switching node that supplies power to the output. Connect

the output LC filter from SW to the output load. Note that a capacitor is required from SW to BS

to power the high-side switch.

4

GND

Ground. Connect the exposed pad on backside to Pin 4.

5

FB

Feedback Input. FB senses the output voltage to regulate said voltage. Drive FB with a

resistive voltage divider from the output voltage. The feedback threshold is 0.92V. See Setting

the Output Voltage

6

COMP

Compensation Node. COMP is used to compensate the regulation control loop. Connect a

series RC network from COMP to GND to compensate the regulation control loop. In some

cases, an additional capacitor from COMP to GND is required. See Compensation

7

EN

Enable/UVLO. A voltage greater than 2.9V enables operation. For complete low current

shutdown the EN pin voltage needs to be at less than 900mV. When the voltage on EN

exceeds 1.2V, the internal regulator will be enabled and the soft-start capacitor will begin to

charge. The MP2372 will start switching after the EN pin voltage reaches 2.9V.

8

SS

Soft-Start Control Input. SS controls the soft start period. Connect a capacitor from SS to GND

to set the soft-start period. A 0.1μF capacitor sets the soft-start period to 10ms.