# Zener diode

Discussion in 'Electronics Homework Help' started by TR-tr, Jun 14, 2015.

1. ### TR-tr

3
0
Jun 14, 2015
As given in the figure below, power rating and the zener voltage of the two zener diodes (Z1 & Z2) used in circuit are 1 W & 10 V and 0.6 W & 6 V respectively. Minimum zener current needed for the satisfactory operation of both zener diodes is 2 mA.

1. If the battery has no internal resistance, find the range of RL values in which the circuit can be used as a voltage regulator satisfactory.

2. What would happen to the operation of the zener diodes if the battery emf is changed to 10 V?

3
0
Jun 14, 2015
Helppp me

3. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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Jan 21, 2010
How far have you got already?

4. ### TR-tr

3
0
Jun 14, 2015
1. I thought 6 V apply on the RL resistance, when Z2 & Z1 have minimum currents. Then I found current through the R1 and then current through RL. Then I found minimum value of RL such that when Z2 & Z1 have maximum currents, I found maximum RL.

2. When emf changed to 10 V zener diodes wouldn't work in breakdown region

Am I correct?

5. ### Colin Mitchell

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Aug 31, 2014
You don't have to worry about the..................

[mod edited]

Last edited by a moderator: Jun 15, 2015
6. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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Jan 21, 2010
Colin, have you read the bit about helping but not doing people's homework for them?

7. ### Ratch

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Mar 10, 2013
I just wanted to point something out. R1 has 90 volts across it, right? That means around 0.18 amps will be present in the 10 volt diode. So the 1 watt diode will be dissipating 1.8 watts. Not good.

Ratch

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