MP2459 – 0.5A, 55V, 480kHz, STEP-DOWN CONVERTER IN A TSOT23-6

MP2459 Rev. 1.0

www.MonolithicPower.com

8

3/4/2013

MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

© 2013 MPS. All Rights Reserved.

PIN FUNCTIONS

Pin #

Name Description

1

BST

Bootstrap. Connect a capacitor between the SW and BS pins to form a floating supply across

the power switch driver. This capacitor drives the power switch’s gate above the supply voltage.

2

GND

Ground. Voltage reference for the regulated output voltage. Requires special layout

considerations. Isolate this node from the D1 to C1 ground path to prevent switching current

spikes from inducing.

3

FB

Feedback. Sets the output voltage. Connect to the tap of an external resistor divider from the

output to GND. The frequency foldback comparator lowers the oscillator frequency when the FB

voltage is below 250mV to prevent current-limit runaway during a short-circuit fault.

4

EN

100k

resistor.

5

IN

Supply Voltage. The MP2459 operates from a 4.5V-to-55V unregulated input. Requires C1 to

prevent large voltage spikes from appearing at the input.

6

SW

Switch Output.