GENERAL DESCRIPTION

The MON35W42 is an enhanced version of the MON35W41 hardware status monitoring IC. The MON35W42 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 the stability and proper operation of high-end computer systems. MON35W42 provides both ISA and I2C serial bus interface.

FEATURES

◾ Monitoring Items

- 3 Thermal Inputs From Remote Thermistors or 2N3904 NPN-type Transistors or Pentium® II (Deschutes) Thermal Diode Output

- 9 Voltage Inputs - Typical for Vcore, +3.3V, +12V, -12V, +5V, -5V, +5V Vsb, Vbat, and One Reserved

- 3 Fan Speed Monitoring Inputs

- Case Open Detection Input

- WATCHDOG Comparison of all Monitored Values

- Programmable Hysteresis and Setting Points (Alarm Thresholds) for all Monitored Items

◾ Action Enabling

- Beep Tone Warning

- 4 PWM (Pulse Width Modulation) Outputs for Fan Speed Control (3 are MUX Optional); Up to 3 sets of fan Speed Monitoring and Control.

- Issue nSMI, nOVT, nGPO Signals to Activate System Protection

- Warning Signal Pop-Up for Application Software

◾ General

- ISA and I2C Serial Bus Interface

- 5 VID Input Pins for CPU Vcore Identification (for Pentium® II)

- Initial Power Fault Beep (for +3.3V, Vcore)

- Master Reset Input to MON35W42

- Independent Power Plane of Digital Vcc and Analog Vcc (Inputs to IC)

- 3 Pins (IA0, IA1, IA2) to Provide Selectable Address Setting for Application of Multiple Devices (up to 8 Devices) Wired Through I2C Interface

- Intel® LDCM (DMI Driver 2.0) Support

- Acer ADM (DMI Driver 2.0) Support

- SMSC Hardware Monitoring Application Software (Hardware Doctor) Support, for Both Windows 95/98 and Windows NT 4.0/5.0

- Input Clock Rate Optional for 24, 48, 14.318 MHz

- 5V Vcc Operation

◾ Package

- 48 Pin TQFP