MP2497 – 3A, 50V, 100kHz STEP-DOWN CONVERTER

MP2497 Rev. 1.12

www.MonolithicPower.com

4

12/22/2011

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PIN FUNCTIONS

Package

Pin #

Name

Description

1

VIN

the IC as possible. It is the drain of the internal power device and power supply for the

whole chip.

2

GND,

Exposed

Pad

Ground. This pin is the voltage reference for the regulated output voltage. For this reason

ground path to prevent switching current spikes from inducing voltage noise into the part.

Connect exposed pad to GND plane for optimal thermal performance.

3

FB

Feedback. An external resistor divider from the output to GND tapped to the FB pin sets

the output voltage. To prevent current limit run away during a short circuit fault condition

the frequency-fold-back comparator lowers the oscillator frequency when the FB voltage

is below 250mV.

4

OVP

Output Over Voltage Protection. Connect OVP to the center point of an external resistor

divider from output to GND. The OVP reference is 1.23V.

5

ISN

Negative Current Sense Input. It is used for load current limiting and output line drop

compensation.

6

ISP

Positive Current Sense Input. It is used for load current limiting and output line drop

compensation.

7

BST

Bootstrap. This capacitor is needed to drive the power switch’s gate above the supply

voltage. It is connected between SW and BST pins to form a floating supply across the

power switch driver. An on-chip regulator is used to charge up the external boot-strap

capacitor. If the on-chip regulator is not strong enough, one optional diode can be

connected from IN or OUT to charge the external boot-strap capacitor.

8

SW

Switch Output. It is the source of power device.