MIC2590B-2YTQ datasheet(5/23 Pages) MICREL | Dual-Slot PCI Hot Plug Controller

5 / 23 page

Micrel, Inc.

MIC2590B

September 2008

M9999-091808

Pin Number

Pin Name

Pin Function

1, 36

/FAULTA, /FAULTB

Open Drain, Active-Low: Asserted whenever the circuit breaker trips due to a

fault condition.

/FAULT[A/B] is reset by bringing the faulted slot’s ON pin low if /FAULT was

asserted in response to a fault condition on one of the slot’s MAIN outputs(+12V,

+5V, +3.3V, or –12V).

/FAULT[A/B] is reset by bringing the faulted slot’s AUXEN pin low if /FAULT was

asserted in response to a fault condition on the slot’s VAUX output.

If a fault condition occurred on both the MAIN and AUX outputs of the same slot,

then both ON and AUXEN must be brought low to de-assert the /FAULT output.

2, 35

CFILTERA, CFILTERB

Filter Capacitor [A/B]: Capacitors connected between these pins and ground set

the duration of tFLT. tFLT is the amount of time for which a slot remains incurrent-

limit before its circuit breaker is tripped.

/INT

Interrupt Output: Open Drain, Active-low. Asserted whenever a power faulti s

detected. Cleared by writing a logic 1 to the respective active bit into the Status

SDA

SMBus Data: Bidirectional SMBus data line.

SCL

SMBus Clock: Input.

39, 40, 41

A2, A1, A0

SMBus Address Select pins: Connect to ground or leave open in order to

program device SMBus base address. There is an internal pull-up to VSTBY on

each of these inputs.

4, 38

GPIA, GPIB

General Purpose Inputs: The state of these inputs are available by reading the

Common Status Register.

GND

Ground

MIC2590B-2YTQ Datasheet(PDF) 5 Page - Micrel Semiconductor