MP2307 – 3A, 23V, 340KHz SYNCHRONOUS RECTIFIED STEP-DOWN CONVERTER

MP2307 Rev. 1.7

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5

3/14/2006

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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 0.01µF 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 4.75V to 23V 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 to Pin 4).

5

FB

Feedback Input. FB senses the output voltage and regulates it. Drive FB with a resistive

voltage divider connected to it from the output voltage. The feedback threshold is 0.925V. 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. In some cases, an additional capacitor from COMP to

GND is required. See Compensation Components.

7

EN

Enable Input. EN is a digital input that turns the regulator on or off. Drive EN high to turn on

the regulator; low to turn it off. Attach to IN with a 100kΩ pull up resistor for automatic startup.

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 15ms. To disable the

soft-start feature, leave SS unconnected.