Dual channel digital thermometer and overlow/overtemperature alarm

     The ADT7461A is a dual channel digital thermometer and hyperthermia/overtemperature alarm for pc and thermal management systems. It is compatible with pins and registers of the ADM1032 and ADT7461. It features series resistance cancellation, where resistors up to 1.5k (typical) in series with a temperature monitoring diode are automatically cancelled out from the temperature result, allowing noise filtering.

     The ADT7461A features a configurable ALERT output and an extended switchable temperature measuring range. It can also measure the temperature of the remote thermal diode to accuracy of ±1°C and the ambient temperature to accuracy of ±3°C. The temperature measurement range defaults to 0°C to +127°C, compatible with the ADM1032, but it can be switched to a wider measurement range of -64 °C to +191°C.

     The ADT7461A communicates through a 2-wire serial interface and is compatible with the System Management Bus (SMBus) standard. Its SMBus default address is 0x4C. The ADT7461A−2 is configured, and the SMBus address is 0x4D. This is useful if more than one ADT7461A is used on the same SMBus. Alarm output signal when temperature on chip or remote is out of range. The THERM output is a comparator output that allows the control cooling fan to be turned on/off. The ALERT output can be reconfigured as a second THERM output if necessary.