Micrel, Inc.

MIC4720

May 2007

3

M9999-051707

Pin Description

Pin Number

MLF

®

Pin Number

MSOP

Pin Name

Pin Function

1,12

1, 10

SW

Switch (Output): Internal power P-Channel MOSFET output switch

2,11

2, 9

VIN

Supply Voltage (Input): Supply voltage for the source of the internal P-channel

MOSFET and driver.

Requires bypass capacitor to GND.

3,10

8

PGND

Power Ground. Provides the ground return path for the high-side drive current.

4

3

SGND

Signal (Analog) Ground. Provides return path for control circuitry and internal

reference.

5

4

BIAS

Internal circuit bias supply. Must be bypassed with a 0.1µF ceramic capacitor to

SGND.

6

5

FB

Feedback. Input to the error amplifier, connect to the external resistor divider

network to set the output voltage.

7

—

NC

No Connect. Not internally connected to die. This pin can be tied to any other pin

if desired.

8

6

EN

Enable (Input). Logic level low, will shutdown the device, reducing the current

draw to less than 5µA.

9

7

PGOOD

Power Good. Open drain output that is pulled to ground when the output voltage

is within +/- 7.5% of the set regulation voltage

EP

—

GND

Connect to ground.