All About Circuits

Opamp Feedback problem, Urgent !!

J

Thread Starter

jaiminajmeri

Joined Sep 4, 2013
1
Opamp Feedback problem, Urgent !!

C1.jpg

1) At resistor R3, Voltage at R3 is 5V initially.
But, After the feedback this voltage changes to 500mV. Can somebody explain this with equations ?

see the ckt here : http://imageshack.us/a/img163/1629/v3hq.jpg

----------------------------

C2.jpg

2) If I replace Voltage@ R3(5V) with 5V battery, then after feedback the voltage remains 5V itself, Any reason ?

see the ckt here : http://imageshack.us/a/img35/3219/a9nc.jpg​
 
#12

#12

Joined Nov 30, 2010
18,224
1) input voltage higher than supply voltage = broken amplifier.
2) battery voltage + output of broken amplifier/1000 ohms = battery voltage
 
You must log in or register to reply here.
Thread starter Similar threads Forum Replies Date
A Why the offset of source-follower（which connected to the output of opamp as voltage buffer) will limit the op-amp output swing ？ Homework Help 0
G Issues with opamp when changing to multiple feedback resistors in series Analog & Mixed-Signal Design 15
A Need help understanding this LDO topology PCB Layout , EDA & Simulations 6
R Mosfet as LED driver in feedback loop of opamp? Analog & Mixed-Signal Design 12
busevaran Trying to control a motor speed with a PID circuit. Analog & Mixed-Signal Design 14
Similar threads
Why the offset of source-follower（which connected to the output of opamp as voltage buffer) will limit the op-amp output swing ？
Issues with opamp when changing to multiple feedback resistors in series
Need help understanding this LDO topology
Mosfet as LED driver in feedback loop of opamp?
Trying to control a motor speed with a PID circuit.

You May Also Like

Top