a thermal anemometer that separates sensor heating from sensor temperature measurement through a switched sampling technique . this approach demonstrates several advantages over the more typical circuitry employing a bridge , which simultaneously heats the sensor and senses the ambient and velocity sensor temperature . in a thermal anemometer in accordance with the present invention , sensor temperature is determined by sampled measurement of its resistance . sensor temperature is controlled by varying the voltage applied to the sensor with an error value determined by the difference between actual sensor resistance and the desired resistance .