GENERAL DESCRIPTION
VREF and the voltage across REXT are measured and converted to a pulse. The microcontroller initiates a conversion by pulling the I/O pin low and releasing it. When conversion is done, the MAX6691 signals the end of conversion by pulling the I/O pin low once again. The pulse corresponding to the first thermistor is sent immediately after the release of the I/O pin. The on-chip power-management circuitry reduces the average thermistor current to minimize errors due to thermistor self-heating. Between conversions, the MAX6691 falls into a 10µA (max) sleep mode, where the voltage reference is disabled and the supply current is at its minimum. The MAX6691 is available in a 10-pin µMAX package and is specified from -55°C to +125°C temperature range. o Simple Single-Wire Interface o Measures Up to Four Thermistor Temperatures o Low-Average Thermistor Current Minimizes SelfHeating Errors o Internal Voltage Reference Isolates Thermistor from Power-Supply Noise o Accommodate...