AME

4

AME5269

Rev. B.01

2A, 28V, 340KHz Synchronous

Rectified Step-Down Converter

n Pin Description

SOP-8

Pin Number

Pin Name

Pin Description

1

BS

High-Side Gate Drive Boost Input. BS supplies the drive for the high-side N-

Channel MOSFET switch. Connect a 0.01

µF 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 28V power source. Bypass IN to

GND with a suitable large capacitor to eliminate noise on the input to the IC.

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 to regulate that voltage. Drive

FB with a resistive voltage divider from the output voltage. The feedback

reference voltage is 0.925V.

6

COMP

Compensation Node. COMP is used to compensate the regulation control

loop. Connect a series RC network from COMP to GND to compensate the

regulation control loop. In some cases, an additional capacitor from COMP to

GND is required.

7

EN

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

higher than 2.7V to turn on the regulator, drive it lower than 1.1V to turn it off.

Pull up to the IN pin with 100K

Ω resister for automatic start up.

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. Add a 0.1uF capacitor set the

soft-start period to 15mS. To disable the soft start feature, leave the SS

unconnected.