Exponential conversion circuit

摘要

A first voltage conversion circuit converts first and second reference input voltages into first and second differential output voltage.A second voltage conversion circuit converts the first reference input voltage and a control input voltage into a third differential output voltage.The third differential output voltage is inputted to an exponential conversion element.The first and second differential output voltages are inputted to an active impedance bridge. The active impedance bridge outputs a gain control voltage of the first and second voltage conversion circuits.A balanced condition of the active impedance bridge determines the exponential conversion characteristic of the output current to the control input voltage of the exponential conversion element.