Local/Remote Temperature Switches in a µMAX Package

The MAX6687/MAX6688 comprise a remote-junction temperature switch and a local temperature switch in a single package. The remote-junction switch uses an external P-N junction (typically a diode-connected transistor on the die of an external CPU, ASIC, or FPGA) as a sensing element to measure the remote temperature. The remote-junction temperature switch has a factory-programmed trip temperature threshold of either +120°C or +125°C. The local temperature switch has a pin-programmable temperature threshold that is set by connecting pins S1 and S2 to ground, to VDD, or leaving them floating. Hysteresis for both local and remote thresholds is 5°C. The MAX6687/MAX6688 do not assert on transient (single-sample) faults or when power is first applied.

The MAX6687 has two open-drain active-low outputs while the MAX6688 has two push-pull active-high outputs. TREMOTE asserts a logic signal when the remote temperature exceeds the factory-programmed +120°C or +125°C trip threshold. TLOCAL is asserted when the die temperature exceeds the pin-programmed threshold, which is controlled by pins S1 and S2. The local thresholds are available in two ranges in 5°C increments. The two ranges are +40°C to +80°C and +75°C to +115°C.

The MAX6687/MAX6688 operate from a 3.0V to 5.5V power supply and are available in a space-saving 8-pin µMAX package.

Applications

* CPU Temperature Protection * Fan Control * FPGA Temperature Protection * Temperature Alarms

* Pin-Programmable Local Temperature Threshold in 5°C Increments in Two Distinct Ranges: +40°C to +80°C and +75°C to +115°C

* Factory-Programmed Remote Threshold: +120°C (L Suffix) or +125°C (H Suffix)

* Open-Drain Active-Low Outputs (MAX6687)

* CMOS Push-Pull, Active-High Outputs (MAX6688)

* ±1.5°C Accuracy

* 2Hz Temperature Sampling Rate

* 215µA Average Supply Current

* 3.0V to 5.5V Power-Supply Voltage

* 8-Pin µMAX Package