MAX6692

19-2545; Rev 1; 10/02 Precision SMBus-Compatible Remote/Local Temperature Sensors with Overtemperature Alarms General Description The MAX6648/MAX6692 are precise, two-channel digital temperature sensors. They accurately measure the temperature of their own die and a remote PN junction, and report the temperature in digital form using a 2-wire serial interface. The remote PN junction is typically the emitter-base junction of a common-collector PNP on a CPU, FPGA, or ASIC. The 2-wire serial interface accepts standard System Management Bus (SMBus)™ write byte, read byte, send byte, and receive byte commands to read the temperature data and to program the alarm thresholds. To enhance system reliability, the MAX6648/MAX6692 include an SMBus timeout. A fault queue prevents the ALERT and OVERT outputs from setting until a fault has been detected one, two, or three consecutive times (programmable). The MAX6648/MAX6692 provide two system alarms: ALERT and OVERT. ALERT asserts when any of four temperature conditions are violated: local overtemperature, remote overtemperature, local undertemperature, or remote undertemperature. OVERT asserts when the temperature rises above the value in either of the two OVERT limit registers. The OVERT output can be used to activate a cooling fan, or to trigger a system shutdown. Measurements can be done autonomously, with the conversion rate programmed by the user, or in a singleshot mode. The adjustable conversion rate allows the user to optimize su...