EC5116

E-CMOS Corp. (www.ecmos.com.tw)

7I26N-Rev. F001

3A, 40V Asynchronous Step-Down Converter

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Pin Description

PIN

SOP8

Name

Description

1

SW

SW is the switching node that supplies power to the output. Connect the output LC filter from

SW to the output load.

2

EN

Drive EN pin high to turn on the regulator and low to turn off the regulator.

3

COMP

Compensation pin. Comp is used to compensate the regulation control loop. Connect a series

RC network from COMP to GND to compensate the regulation control loop. One ceramic cap

such as several tens pF is usually connected from COMP to GND to decouple the voltage noise

.

4

FB

Output feedback pin. FB senses the output voltage and is regulated by the control loop to FB

reference voltage 0.8V. Connect a resistive divider at FB.

5

GND

Ground.

6

RT

Voltage at the RT pin is regulated at 1.2V. Switch frequency of the regulator can be adjusted by

connecting a resistor at the RT pin to ground.

7

VIN

Input voltage pin. VINsupplies power to the IC. Connect a 3.8V to 40V supply to VIN and

bypass VIN to GND with a suitably large capacitor to eliminate noise on the input pin to the IC.

8

BST

Bootstrap pin for top switch. A 0.1uF or larger capacitor should be connected between this pin

and SW pin to supply current to the top switch and top switch driver.

Block Diagram