Micrel, Inc.

MIC28510

March 2012

2

M9999-030912-A

Ordering Information

Part Number

Junction Temperature Range

Package

Lead Finish

MIC28510YJL

40C to 125C

28-pin 5mm

Pb-Free

Pin Configuration

28-Pin 5mm

Pin Description

Pin Number

Pin Name

Pin Function

1, 3

NC

No Connect.

2, 5, 6,

7, 8, 21

PGND

Power Ground. PGND is the ground path for the MIC28510 buck converter power stage. The

PGND pin connects to the sources of low-side N-Channel internal MOSFETs, the negative

terminals of input capacitors, and the negative terminals of output capacitors. The loop for the

power ground should be as small as possible and separate from the signal ground (SGND) loop.

4, 9, 10,

11, 12

SW

Switch Node (Output). Internal connection for the high-side MOSFET source and low-side

MOSFET drain.

13, 14, 15, 16,

17, 18, 19

PVIN

High-Side Internal N-Channel MOSFET Drain Connection (Input).The PVIN operating voltage

range is from 4.5V to 75V. Input capacitors between the PVIN pins and the power ground (PGND)

are required and keep the connection short.

20

BST

Boost (Output). Bootstrapped voltage to the high-side N-channel internal MOSFET driver. A

Schottky diode is connected between the VDD pin and the BST pin. A boost capacitor of 0.1μF is

connected between the BST pin and the SW pin.

22

CS

Current Sense (Input). High current output driver return. The CS pin connects directly to the switch

node. Due to the high-speed switching on this pin, the CS pin should be routed away from

sensitive nodes. CS pin also senses the current by monitoring the voltage across the low-side

internal MOSFET during OFF-time.