Semiconductor Fundamentals Unit 4 – Diode Wave Shaping and Zener Regulation
In circuits, the zener current (IZ) is limited to a safe value by a resistor (R2) in series with the
zener (CR1).
A zener diode (CR1) can be configured in a circuit to control the out-put voltage (VO) so that it
equals the zener voltage (VZ).The zener diode voltage regulator maintains the output voltage
(VO) equal to the zener voltage for changes in the input (line) voltage (VA)and load current (IL).
NEW TERMS AND WORDS
limiter - circuits that prevent voltage above or below a specified point from appearing at circuit
output terminals.
clamper - circuits that shift the reference level of a waveform from input to circuit output.
zener diode - a diode designed to operate in the avalanche region, maintaining a relatively
constant voltage drop over a range of current flows. The avalanche operating area of a diode
occurs when the cathode is positive with respect to the anode.
zener voltage - the nearly constant voltage produced by a zener diode.
voltage regulator - an IC that maintains a constant output voltage when both input voltage and
output loads change.
dc restorers - circuits that duplicate their input voltage at their output terminals but move or shift
the signal reference level; also called level shifters.
positive clamper - a circuit that sets or clamps the negative peaks of an input waveform.
negative clamper - a circuit that sets or clamps the positive peaks of an input waveform.
avalanche - the reverse voltage point where a PN junction breaks down to pass high values of
current.