MAX6656MEE

The MAX6656 is a precise voltage and temperature monitor. The digital thermometer reports the temperature of two remote sensors and its own die temperature. The remote sensors are diode-connected transistors-typically a lowcost, easily mounted 2N3906 PNP type-that replace conventional thermistors or thermocouples. Remote accuracy is ±1°C for multiple transistor manufacturers with no calibration necessary. The remote channels can also measure the die temperature of other ICs, such as microprocessors, that contain a substrate-connected PNP with its collector grounded and its base and emitter available for temperature-sensing purposes. The temperature is digitized with 11-bit resolution.

The MAX6656 also measure it's own supply voltage and three external voltages with 8-bit resolution. Each voltage input's sensitivity is set to give approximately 3/4-scale output code when the input voltage is at its nominal value. The MAX6656 operates on a +3.3V supply and its second voltage monitor is 5V.

The 2-wire serial interface accepts standard SMBus™ Write Byte, Read Byte, Send Byte, and Receive Byte commands to program the alarm thresholds and to read data. The MAX6656 also provide SMBus alert response and timeout functions. The MAX6656 measures automatically and autonomously, with the conversion rate programmable. The adjustable rate allows the user to control the supply current.

In addition to the SMBus ALERT -bar output, the MAX6656 features an OVERT -bar output, which is used as a temperature reset that remains active only while the temperature is above the maximum temperature limit. The OVERT-bar output is optimal for fan control or for system shutdown.