# zener diode in series

Discussion in 'Homework Help' started by stones, Oct 12, 2015.

1. ### stones Thread Starter New Member

Aug 15, 2015
2
0
If two Zener diodes are connected in series and if there is an ac input voltage ,how varies the output voltage ?

2. ### crutschow Expert

Mar 14, 2008
12,566
3,080
Show us the circuit.

Aug 15, 2015
2
0
4. ### pwdixon Member

Oct 11, 2012
488
56
You should get a limited sinewave with the limits at +(5.1V+0.7V) and -(3.3V+0.7V), roughly.

5. ### WBahn Moderator

Mar 31, 2012
17,457
4,701
What you need to do (other than just parroting some answer to your homework) is develop the DC transfer characteristic for the circuit. To do this, you need to consider what the output voltage is for different states of the two diodes.

6. ### crutschow Expert

Mar 14, 2008
12,566
3,080
To add to WBahn's post, look at what the voltage is across the two diodes as the input voltage changes over the input voltage range and then what the diodes do as the voltage goes above and below the zener voltages.

Note that one diode is always reverse biased while the other is forward biased and that a zener diode in the forward direction looks like a normal diode

7. ### crutschow Expert

Mar 14, 2008
12,566
3,080
This is a Homework Help section not a Homework Do.
It's preferred that we let the op try to solve the problem with hints from us rather than giving him the answer.

8. ### pwdixon Member

Oct 11, 2012
488
56
Sorry.
I must admit I expected the OP to come back with something like "what are those voltages?" Also must admit I forgot it was the homework forum.