Overview: NCT72 +15C Temperature Monitor with Series Resistance Cancellation
The NCT72 is a dual-channel digital thermometer and
undertemperature/overtemperature alarm, intended for use in PCs and
thermal management systems. It is pin and register patible with the
NCT1008 but the NCT72 allows the user to pull the ALERT pin to
1.8 V without increasing the device Idd. A feature of the NCT72 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
NCT72 has a configurable ALERT output and an extended, switchable
temperature measurement range.
The NCT72 can measure the temperature of a remote thermal diode accurate to ±1°C and the ambient temperature accurate to ±3°C. The temperature measurement range defaults to 0°C to +127°C, patible with the NCT1008, but it can be switched to a wider measurement range of −64°C to +191°C.
The NCT72 municates over a 2-wire serial interface, patible with system management bus (SMBus/I2C) standards. The default SMBus/I2C address of the NCT72 is 0x4C. An NCT72D is available with an SMBus/I2C address of 0x4D. This is useful if more than one NCT72 is used on the same SMBus/I2C.
An ALERT output signals when the on-chip or remote temperature is
out of range. The THERM output is a parator output that allows
on/off control of a cooling fan. The ALERT output can be reconfigured
as a second THERM output, if required.
