GENERAL DESCRIPTION

The W83781D/G is a hardware monitoring IC for personal computers, server computers, or microprocessor based systems. W83781D/G can be used to monitor several critical hardware parameters of the system, including power supply voltages, fan speeds, and temperatures, which are very important for a high-end computer system to work stablely and properly. W83781D provides both ISA and I2CTM serial bus interface.

A 8-bit analog-to-digital converter (ADC) was built inside W83781D/G. The W83781D/G can monitor 3 external thermistor temperature sensors, 5 positive analog voltage inputs, two inverting inputs (for monitoring negative voltages), and also three fan tachometer outputs. There is also one input for case open detection circuits.

FEATURES

Monitoring Items

? 3 thermal inputs from remote thermistors

? 5 positive voltage inputs (typical for +12V, +5V, +3.3V, VcoreA, VcoreB)

? 2 op amps for negative voltage monitoring (typical for -12V, -5V)

? 3 fan speed monitoring inputs

? Case open detection input

? WATCHDOG comparison of all monitored values

? Programmable hysteresis and setting points for all monitored items

Actions Enabling

? Warning signal pop up in application software

? Beep tone warning

? Fan ON/OFF control

? Issue SMI#, IRQ to activate system protection

General

? ISA and I2CTM serial bus interface

? 5 VID input pins for CPU Vcore identification

? Initial power fault beep (for +3.3V, VcoreA)

? Master reset input to W83781D/G

? Independent power plane of digital Vcc and analog Vcc (input to IC)

? Intel LDCMTM compatible

? Winbond monitoring application software support

? Input clock rate optional for 24, 48, 14.318 MHz

Package

? 48-pin LQFP