Operate in breakdown to hold a nearly constant voltage.
A Zener diode conducts in reverse at a specified voltage V_Z, holding it nearly constant. With series resistor R_s=(V_in-V_Z)/(I_Z+I_L). Simple reference or regulator for small loads; poor efficiency and temperature drift versus IC regulators.
A 5.1 V Zener protects an input from over-voltage.
A Zener diode holds a voltage nearly constant in reverse breakdown, which makes a simple reference or regulator for small loads.
Operate in breakdown to hold a nearly constant voltage.
A Zener diode holds a voltage nearly constant in reverse breakdown, which makes a simple reference or regulator for small loads.
A series resistor passes the current, and the Zener holds the output voltage at its breakdown value as long as the current stays within its range.
The series resistor wastes power as heat, which becomes large for big loads, so it is used only for small currents.
Typical applications include creating a 5.1 V reference for an ADC input, protecting a 3.3 V pin from overvoltage spikes and building a basic regulator for a low-current sensor.
Study "Filters and smoothing" first (topic 6 of 104 in Electronics & Embedded). It covers the groundwork this topic builds on.
Minimum Zener current. Power rating P=V_Z·I_Z. Low-noise reference types.
A 5.1 V Zener protects an input from over-voltage.
The next topic is "LEDs and photodiodes", which builds directly on this one.
It is classed as Beginner in Electronics & Embedded (topic 7 of 104). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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