Do you know the series-parallel characteristics of the regulator diode?

Problem of connecting two zener diodes in series and in parallel

Known: The stabilizing values of the two zener diodes are 8V and 6V respectively, and the forward conduction voltage is both 0.7V

Question: After two zener diodes are connected in series and in parallel respectively, how many voltages are there? What are they? The forward conduction voltage of the zener diode is 0.7V, and the reverse direction is the regulated value.

series

1. Both diodes are connected in reverse, and the reverse voltage is a regulated value, which is 68 = 14V

2. The positive connection of 6V, the negative connection of 8V, the positive connection is 0.7V, and the negative connection is 8V, so that 80.7 =8.7V

3. Similarly, 6V is connected in reverse, 8V is connected in positive, 60.7 =6.7V

4. Both diodes are connected in reverse to 0.7 0.7=1.4V

parallel

1. Both diodes are connected in reverse, and the voltage is small, but the pilot is turned on, which is 6V

2. One is connected forward and the other is connected reverse. If the voltage is small, the voltage is 0.7V

How to calculate 2 zener diodes in parallel

There are 4 types of parallel circuits for two voltage regulators, and there are only two types of parallel voltages for the two voltage regulators connected in parallel: 6V and 0.7V. See the following figure:

Problem of connecting two zener diodes in series and in parallel

Type: Two voltage stabilizing diodees are connected with reverse bias, and only the diodee with low voltage stabilizing value is broken down to form a 6V voltage stabilizing value. The other three circuits have at least one regulator diodee in positive bias, so the positive bias pipeline is turned on, making its voltage =0.7V. If connected in series, it is the sum of the two.

The effect of reverse series connection

1. Often in amplification circuits with high power, the base b of the power diodee and the emitter e, that is, the emitter junction, are connected in parallel with two inverted diodes, which protects the input current of the emitter junction;

2. After two diodes are connected in reverse in series, they can protect the circuit connected in parallel. When the circuit is over-voltage, the diode first breaks down and shorts;

Bi-directional overvoltage protection. This bidirectional tvs, bidirectional overvoltage protection circuit is generally used in electronic circuits, connected in parallel with the protected PN junction to protect the PN from reverse overvoltage;

Function: overvoltage protection, electrostatic protection, voltage clamping, damping effect.