The TMP401 is a remote temperature sensor monitor with a built-in local temperature sensor. The remote sensor is capable of monitoring the temperature of any external PN junction. Typical sense elements include low-cost NPN- or PNP-type transistors and diodes, or accessible thermal diodes integrated within microcontrollers, microprocessors,or field-programmable gate arrays (FPGAs).The accuracy of the remote sensor is ±1°C for multiple IC manufacturers, with no calibration needed.The two-wire serial interface accepts SMBus write byte, read byte, send byte, and receive byte commands to program alarm thresholds and to read temperature data.Features included in the TMP401 are series resistance cancellation, wide remote temperature measurement range (up to +150°C), diode fault detection, and temperature alert functions.