eorex

EP3101

Jul. 2006

www.eorex.com

2/13

Pin Assignment

1

EN

23

45

SW

GND

FB

TO220-5L

Ordering Information

Buck Regulator

Package

Packing

EP3101 -X X X

: TO263-5L

Blank: Adj

50 = 5V

33 = 3.3V

12 = 12V

R: Taping & Reel

B: Bag

: TO220-5L

Pin Description

Pin

Name

Function

1

This is the positive input supply for the IC switching regulator. A suitable

input bypass capacitor must be present at this pin to minimize voltage

transients and to supply the switching currents needed by the regulator.

2

SW

minimize coupling to sensitive circuitry, the PC board copper area

connected to this pin should be kept a minimum.

3

GND

Circuit ground.

4

FB

Senses the regulated output voltage to complete the feedback loop.

5

EN

Low enable. Allows the switching regulator circuit to be shutdown using

logic level signals thus dropping the total input supply current to

approximately 150uA. Pulling this pin below a threshold voltage of

approximately 1.3V turns the regulator on, and pulling this pin above

1.3V (up to a maximum of 40V) shuts the regulator down. If this

shutdown feature is not needed, the EN pin can be wired to the ground

pin or it can be left open, in either case the regulator will be in the ON

condition.