Zener Diodes and Op-Amps

WoAiMeiMei SG

All Solved

1) Ok

2)Ok

3) Ok

4) Ok

http://i39.tinypic.com/vzhufd.jpg

syncopation_music SG

Your question 1 is simple

recall what is the forward voltage of Zener ?

then you will be able to find the answer

the question 2 is zener = 0 ohm ,mean its a short ... shorted zener is just a piece of wire

remember ?

I graduate from Ngee Ann Polytechnic ,Dip in Electronics and Computer Engineering

syncopation_music SG

question 3 .. pls refer to wikipedia.com on wheatstone bridge :) suppose you forgotten the simple formulae :)

just wiki on "wheatstone bridge" and the answer will be given

wheatstone is the perequisite for the principle behind an Galvanometer

syncopation_music SG

question 4 is a voltage divider /integrator or differentiator circuit [ i cant exactly remember ]

there is a simple formulae for this

check them out in the Poly library

u can check boylestad, paynter or bogart books on electronics device :)

wiki i dun think can find ... becos so far no one contribute mass scale on op-amp topics

something to help u

http://en.wikipedia.org/wiki/Operational_amplifier

WoAiMeiMei SG

I don't actually study in singapore so my course curriculum would be slightly different. ie. we never actually cover wheatstone bridges but thank god for wiki! lol

Q4 im still in the dark, especially when given a circuit which is not like the normal ones.

When looking at Q2, if Vr = 0, would that mean our circuit comprises of just a Vs, RA and RL? Then how do we deal with the information given for Vz, And Iz (max/min)

Q1) is forward V = 0.7?

syncopation_music SG

if looking at a certain way ...it mean something

let me check first

WoAiMeiMei SG

stuck.. on the first 2 -.-

WoAiMeiMei SG

with a test this friday, gg.. ><

every1 must be having tests and exams now

WoAiMeiMei SG

Ok, i got

3) as R4= (R2/R1 ). R3

1) (Vs - Vz / Ra) x Vz

got 1 .. yes! lol!

WoAiMeiMei SG

Q4), first part i achieved by

Rf / V1 = R1

Rf / V2 = R2

with V1 being A and V2 being B

part b not sure... yet

WoAiMeiMei SG

solved it..

Part B = V- = -Rf/R1 (V1)

syncopation_music SG

good ;) you are doing fine :)

WoAiMeiMei SG

What ive done for Q2) which is apparently wrong =.=

(Vs x 0.75 )/ Lowest RL (lowest V, lowest R) = Current L

Vs x 1.25 (highest V) / Current L = RA

it's wrong, now what? :s

WoAiMeiMei SG

Q2)

Given R(load) varies [min call X, max call Y] Vs[15,25] Vz= value given call Vz

Iz,max=Is,max-IL,min
=(Vs,max-Vz)/Ra - Vz/Y

Iz,min=Is,min-IL,max
=(Vs,min-Vz)/Ra - Vz/X

Iz,min=0.1(Iz,max)
use graphics calculator and the two eqn's u have from above with the unkown as Ra and out comes the ANSWER to Q2

WoAiMeiMei SG

Problem solved :D thnx