Zener diode detector circuit

摘要

A rectifier circuit comprises two Zener diodes (3,4) having substantially the same characteristic Zener voltage which are connected to receive a sinusoidal input signal via a low impedance buffer (8). A half-wave rectified signal appearing on line (17) has a DC bias equal to the Zener voltage which is removed by the operational amplifier (15). A low pass filter (20) provides a smoothed DC voltage output on line (21). The circuit may be used as an AC to DC converter or for the detection of signals ranging from several volts down to a few millivolts. Its linear response over a wide dynamic range and at small signal levels is an advantage over conventional silicon diode rectifier circuits which suffer distortion at low signal levels.