Back to Forums
6 posts / 0 new
Last post
#1 Dec 13, 2020
ferdymercury
Offline
Last seen: 3 years 10 months ago
Joined: 2020-12-13 12:49

[SOLVED] current source loss of 1pA per volt

Hello, I am new to PSPICE and was wondering if there is a way to make current source ideals. What I am seeing right now is that there is a current leak of about 1pA per volt.

Is there a way to turn off this leakage?

Attached below is the demonstration of the effect. There is only 1pA remaining on the right of the current source I1 when the voltage drop is 1V, and 0pA left when the voltage drop is 2V.

1V.png

2V.png

 

Interestingly enough, with 3V, it starts 'absorbing 1pA current' instead of providing current.

3V.png

In summary, the equation for the current on the right of I1 is:

I1(right) = 2pA - 1pA/V * V1

I verified by adding a dummy voltage source V2 with zero volt (0V) value, and plotting I(V2) vs a DC sweep on V1:

leakage.png

[SOLVED], by changing GMIN from 1p to 0.01p or lower, see below. The explanation of GMIN is in https://resources.pcb.cadence.com/i/1180526-pspice-user-guide/168?

Sun, 2020-12-13 13:17
ferdymercury
Offline
Last seen: 3 years 10 months ago
Joined: 2020-12-13 12:49

I just found this post that might be answering (No) to my question:

https://groups.io/g/LTspice/topic/50142221?p=Created,,,20,2,0,0::,,,0,0,...

Sun, 2020-12-13 13:56
ferdymercury
Offline
Last seen: 3 years 10 months ago
Joined: 2020-12-13 12:49

Ok, I found a solution based on the manual explanation of GMIN being the minimum conductance of any branch.

If I go to Analysis, Setup, Options, and change GMIN from 1p to 0.001p, then the current is 'ideal' enough for my application.

Mon, 2020-12-14 15:02 (Reply to #3)
Mohammadreza_adib
Mohammadreza_adib's picture
Offline
Last seen: 3 years 10 months ago
Joined: 2020-12-13 04:35

thanks for sharing solution!

Mon, 2024-02-12 07:14
priyanka
priyanka's picture
Offline
Last seen: 1 month 3 weeks ago
Joined: 2023-08-23 07:22

These categories are extensive, and they range from body type to Escorts in Amritsar service provided by the girls.

Tue, 2024-10-01 06:16
IngeWakita
Offline
Last seen: 3 weeks 3 days ago
Joined: 2023-02-23 04:20

Your posts are always so lost boys clothing well-structured and easy to follow. Thanks!

Download PSpice and try it for free! Download Free Trial
Cadence