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