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.

Total Gm of OTA versus Frequency

Status
Not open for further replies.

erikl

Super Moderator
Staff member
Joined
Sep 9, 2008
Messages
8,114
Helped
2,694
Reputation
5,368
Reaction score
2,294
Trophy points
1,393
Location
Germany
Activity points
44,060
Run an ac analysis with an ac unit (1V) input voltage, then plot output-current vs. frequency. Output-current in [A] corresponds to Gm in . Or use 1mV input voltage and get [mS] of Gm.
 

an_82

Member level 2
Joined
Oct 6, 2013
Messages
52
Helped
7
Reputation
14
Reaction score
7
Trophy points
8
Location
Delft, Netherlands
Activity points
303
Dear erikl,

I understood what you mean, but I could not get the desired output.

I have two questions:

1. My circuit input is differential and the output is sigle-ended. How do I apply the input? I applied "ac=1 sin(0 1 1meg)" as the input voltage (in open-loop config.).
2. I putted a capacitor at the output. Am I right?

Thanks.
 

erikl

Super Moderator
Staff member
Joined
Sep 9, 2008
Messages
8,114
Helped
2,694
Reputation
5,368
Reaction score
2,294
Trophy points
1,393
Location
Germany
Activity points
44,060
1. This is correct, but works only if your inputs are DC biased to a working operation point (i.e. within the ICMR).
2. This doesn't matter if you measure the output current. It just could decrease the output voltage bandwidth because of slew rate limitation.
 
  • Like
Reactions: an_82

    an_82

    Points: 2
    Helpful Answer Positive Rating
Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top