Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

[Moved]: what's the function of the feedback resistor Rf in this circuit

Status
Not open for further replies.
S

shanmei

Advanced Member level 1
Joined
Jul 26, 2006
Messages
430
Helped
8
Reputation
16
Reaction score
8
Trophy points
1,298
Location
USA
Activity points
4,496
what's the function of the feedback resistor Rf in this circuit? no current goes through Rf, so why Rf is here? Current I1 will go into the base of BJT.

2.png
 

Re: what's the function of the feedback resistor Rf in this circuit

Look carefully!
Rf is not only connected to the high-resistive opamp input!
 
Re: what's the function of the feedback resistor Rf in this circuit

Oh, I see. The current will go through Rf as well. Thanks.
 

Re: what's the function of the feedback resistor Rf in this circuit

Rf ensures the BJT can be fully turned off.
Without Rf any leakage current through the fet will be amplified through the BJT and flow (uncontrolled) through the output.
 
Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top