The ADT7461A is a dual-channel digital thermometer and undertemperature/overtemperature alarm, intended for use in PCs and thermal management systems. It is pin- and register-compatible with the ADM1032 and ADT7461. A feature of the ADT7461A is series resistance cancellation, where up to 1.5 kW (typical) of resistance in series with the temperature monitoring diode can be automatically cancelled from the temperature result, allowing noise filtering. The ADT7461A has a configurable ALERT output and an extended, switchable temperature measurement range. The ADT7461A can measure the temperature of a remote thermal diode accurate to 1C and the ambient temperature accurate to 3C. The temperature measurement range defaults to 0C to +127C, compatible with the ADM1032, but it can be switched to a wider measurement range of -64C to +191C. The ADT7461A communicates over a 2-wire serial interface, compatible with system management bus (SMBus) standards. The default SMBus address of the ADT7461A is 0x4C. An ADT7461A-2 is available with an SMBus address of 0x4D. This is useful if more than one ADT7461A is used on the same SMBus. An ALERT output signals when the on-chip or remote temperature is out of range. The THERM output is a comparator output that allows on/off control of a cooling fan. The ALERT output can be reconfigured as a second THERM output, if required.