# A zener diode question

Discussion in 'Electronics Homework Help' started by Atakan, Feb 27, 2017.

1. ### Atakan

11
0
Dec 18, 2016
Who can solve this question and where is zener diode's resistance ?

File size:
23.1 KB
Views:
124

2,370
661
Jun 10, 2015
I can.

3. ### Atakan

11
0
Dec 18, 2016
can u explain me how you did? i am needing so.

4. ### AnalogKid

2,370
661
Jun 10, 2015
Since this is a homework problem, first you show us your work. Then we advise.

ak

5. ### Atakan

11
0
Dec 18, 2016
i did 10-5.6 / 100 = 0.044 A = Iz and then 5.6/220+2.2k= 2.3mA=IL and then already vo=vz namely vo=5.6V is it true ?

6. ### duke37

5,364
769
Jan 9, 2011
Put some brackets in your equations to define what should be calculated first. Thus 10-5.6/100 should read (10-5.6)/100

44mA is NOT Iz
5.6/(220+2k2)=2.3mA correct

7. ### Atakan

11
0
Dec 18, 2016
5.6/100= 56mA so that iz=56mA and then il=2.3mA
if i sketch 100ohm's next to ix , namely, ix=iz+iL =2.3mA+56mA= 58.3mA= ix ?????
A question, What is A ? a is 0 or other ?

8. ### duke37

5,364
769
Jan 9, 2011
56mA is the current through the 100Ω resistor. This goes two ways, some through the zener and some through the series resistors (2.3mA) so what is left to go through the zener?

CDRIVE likes this.
9. ### Atakan

11
0
Dec 18, 2016
ix=İz+İL
ix= (10-5.6)/100=44mA
il= 5.6/(220+2200)= 2.3mA
ix-il=iz 44mA-2.3mA= 41.7mA=iz
is it true?
And then what is vo?
Why is there ampermeter? what is value of ampermeter?

10. ### duke37

5,364
769
Jan 9, 2011
The diagram shows Vo=Vz but does not show where the output would be connected.
The meter is to measure the current through the bypass as the resistor is changed.

Atakan likes this.
11. ### Atakan

11
0
Dec 18, 2016
thank you for helping , by the way, is my response true? if you say it , i am pleasure.

12. ### duke37

5,364
769
Jan 9, 2011
All seems to be correct, congratulations.

chopnhack likes this.
13. ### CDRIVEHauling 10' pipe on a Trek Shift3

4,960
648
May 8, 2012
Trevor, I have to click a "LIke" somewhere in this thread but I'm not settled on which of your replies it will be. You did a great job of walking him through the problem without actually doing the work for him.
On second thought it's got to be this one because it ends with a "?". It's reminiscent of how shrinks are depicted when the patient asks ..."Doc, do you think that this has anything to do with my problem"? And the \$100.00/Hr shrink (who never offers and opinion) invariably replies with ... "What do you think"? Atakan, fortunate for you that Duke's therapy is free! Chris

chopnhack likes this.
14. ### Petkan

19
2
Feb 9, 2011
Atakan:

Here is a simple approach:
1. First assume the voltage across the zener is always 5.6V.
2. Calculate the current through its ballast resistor on the left as I=(Vin-Vz)/R
3. Calculate the load current as Vz/(Rload) (assuming ideal A meter with zero resistance)

Last edited by a moderator: Mar 4, 2017
15. ### duke37

5,364
769
Jan 9, 2011
The resistance of a zener diode is used to describe the change in voltage as the current is changed. Often this resistance is taken as zero.
Free?
I was hoping for some Turkish delight.  16. ### Audioguru

2,869
644
Sep 24, 2016
I like Afternoon delight!   