Fan controller with integrated temperature monitoring
The Maxim Integrated MAX6643LBBAEE+T is a fan speed controller and temperature monitor that combines an ADC, PWM generator, and tachometer counter in a single 16-QSOP package. The device outputs a PWM signal to drive a fan and provides an alarm output for overtemperature events. Typical applications include server power supplies, telecom equipment, and industrial enclosures where closed-loop fan speed control based on temperature is required.
Local temperature accuracy is rated at ±3.5°C (max), remote accuracy at ±3°C (max). For a system that needs to keep a processor or power stage below a thermal threshold, this ±3°C window is tight enough to trigger fan spin-up before the junction hits the critical limit, but not tight enough for precision thermal calibration — that would require a ±1°C or better sensor. The supply voltage range of 3V to 5.5V covers both 3.3V and 5V rails common in mixed-voltage designs, so no extra regulator is needed when the fan supply is 5V and the controller runs from 3.3V.
Surface-mount only, ROHS3 compliant per the listing.