A voltage-to-frequency converter design without inherent linearity error suitable for bipolar operation

Owing to the discharge time of their integrating capacitors, the presently available voltage-to-frequency converters exhibit an inherent linearity error of their transfer functions. As will be shown here, this shortcoming can be eliminated by a small extension of the circuitry. The resulting design can then easily be adjusted to bipolar operation. In neither case do corresponding ICs need more external components than the currently available ones. The bipolar device does not require a separate sign output, but uses the output pulse length for sign encoding.