MON35W42

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.

An 8-bit analog-to-digital converter (ADC) is contained within the MON35W42. The MON35W42 can simultaneously monitor 9 analog voltage inputs, 2 fan tachometer inputs, 3 remote temperature and 1 case-open detection signal. The remote temperature sensing can be performed by thermistors, or 2N3904 NPN-type transistors, or directly from Intel^® Deschutes CPU thermal diode output. The MON35W42 provides: 4 PWM (pulse width modulation) outputs for the fan speed control; beep tone output for audio warning and nSMI, nOVT, and nGPO signals for system protection events.

With application software such as the Intel^®  LDCM (LANDesk Client Managemet software, the user can read all the monitored parameters of system from time to time. And a pop-up warning can also be activated when the monitored item drifts out of the proper/preset range. Also the user can set the upper and lower limits (alarm thresholds) of these monitored parameters and activate programmable and maskable interrupts. An optional beep tone can be used as a warning signal when the monitored parameter is out of the preset range.

Additionally, 5 VID inputs are provided to readthe VID of CPU (i.e. Pentium^® II) if applicable. This provides automatic correction of the Vcore voltage. The MON35W42 uniquely provides an optional feature: early stage (before BIOS is loaded) beep warning. This is to detect if a fatal condition is present --- Vcore or +3.3V voltage fail, and the system can not boot up. There are 3 specific pins to provide selectable address settings for applications using multiple devices (up to 8 devices) wired through the I²C interface.