MIC2580A

Micrel, Inc.

MIC2580A

2

February 2005

Pin Configuration

1

12VOUT

3VGATE

3VOUT

3VSENSE

3VIN

/PCIRST

/LPCIRST

/EPWRGD

/PWRGD

VPCHG

24 12VIN

5VGATE

5VOUT

5VSENSE

5VIN

/FAULT

CSTART

CSLEW

/POR

CRST

23

22

21

20

19

18

17

16

15

2

3

4

5

6

7

8

9

10

GND

/ON

11

M12VIN

M12VOUT

12

14

13

24-lead TSSOP (TS)

Pin Description

Pin Number

Pin Name

Pin Function

1

12VOUT

+12V Switched Supply (Output): Load carrying output.

2

3VGATE

3.3V Gate Drive (Output): Drives gate of external N-channel MOSFET +3V

switch. Adding capacitance will slow the slew rate of the external MOSFET

switch turn-on. (The external MOSFET’s gate is charged by an internal

current source.)

3

3VOUT

+3.3V Output Voltage Sense (Input): Connect to source of external

N-channel MOSFET (+3V switched output) to monitor for output undervolt-

age conditions.

4

3VSENSE

+3.3V Current Sense (Input): Measures voltage drop across an external

sense resistor with respect to 3VIN for overcurrent detection through the

+3.3V switch.

5

3VIN

3V Supply (Input): +3.3V-supply input for current monitoring (reference input

for 3VSENSE). Not a load-current carrying input.

6

/PCIRST

PCI-Bus Reset (Input): Input from PCI bus that resets the internal logic.

Ordering Information

Part Number

Precharge

Temperature

Standard

Pb-Free

Voltage

Range

Package

MIC2580A-1.0BTS

MIC2580A-1.0YTS

1V

–40°C to +85°C

24-lead TSSOP

MIC2580A-1.6BTS

MIC2580A-1.6YTS

1.6V

–40°C to +85°C

24-lead TSSOP