摘要 |
A class B amplifier circuit produces a deadband that is independent of semiconductor process variations and creates a positive voltage when a differential input voltage is non-zero. A differential input amplifier couples differential currents representing the differential input voltage to a logarithmic compression circuit, which in turn creates an output voltage that is a function of the differential input voltage and is independent of semiconductor process variations. Transistor devices in the differential amplifier and the logarithmic compression circuit are biased in the non-saturated region of a transistor transfer curve in a weak inversion state. A combination of two comparator circuits compares the output voltage to a reference voltage to create a combined output voltage that is a positive when the input is non-zero.
|