Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic 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

Calculating input and output impedance of an amplifier

Status
Not open for further replies.

uoficowboy

Full Member level 3
Joined
Apr 4, 2009
Messages
168
Helped
6
Reputation
12
Reaction score
4
Trophy points
1,298
Location
Seattle, Wa, USA
Activity points
2,946
I seem to remember a nice set of rules for calculating input and output impedance of an amplifier. Something like:

Treat all capacitors as opens, all voltage sources as shorts, all current sources as ... and then just calculate the resistance between input and ground. Or something like that.

Can anybody remind me of the rules?

Also, generally speaking, I think Ri = delta v/delta i. But what about Ro?

Sorry, it's been a while! :)
 

Sean87

Newbie level 6
Joined
Jan 6, 2012
Messages
13
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Location
Netherlands
Activity points
1,365
@cowboy

Those rules applies for verylow and very high frequencies which capacitors can be thoouht as open or short...You have to be aware of frequency you are dealing with (If I remember correctly :p)
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top