The ADM1032 is a dual-channel digital thermometer and under/overtemperature alarm intended for use in PCs and thermal management systems. The device can measure the temperature of a remote thermal diode, which can be located on the processor die or can be a discrete device (2N3904/06), accurate to 1C. A novel measurement technique cancels out the absolute value of the transistor's base emitter voltage so that no calibration is required. The ADM1032 also measures its ambient temperature. The ADM1032 communicates over a 2-wire serial interface compatible with System Management Bus (SMBus) standards. Under/overtemperature limits can be programmed into the device over the SMBus, and an ALERT output signals when the on-chip or remote temperature measurement is out of range. This output can be used as an interrupt or as a SMBus alert. The THERM output is a comparator output that allows CPU clock throttling or on/off control of a cooling fan. An ADM1032-1 and ADM1032-2 are available. The difference between the ADM1032 and the ADM1032-1 is the default value of the external THERM limit. The ADM1032-2 has a different SMBus address. The SMBus address of the ADM1032-2 is 0x4D.