I'm working through the tutorial on this page:
http://www.allaboutcircuits.com/vol_3/chpt_3/8.html
Near the top of the page, the first Spice example and graph. I've duplicated that netlist, but used a real diode model. Here is my netlist (ngspice notation):
using tran 0.01m 10m (just a little longer than the given example). Got the same graphs, no problem.
My question concerns the current through node 1. I plotted that and zoomed in to find that it is a triangle wave, 10uA peak, at about 50KHz.
Hmm. I'm thinking maybe the current is leakage from the diodes? But I can't explain the shape or frequency. Can someone tell me where that current is coming from and why that shape and frequency?
I'm new to Spice, so maybe I did something wrong?
Thanks,
Keith Ostertag
http://www.allaboutcircuits.com/vol_3/chpt_3/8.html
Near the top of the page, the first Spice example and graph. I've duplicated that netlist, but used a real diode model. Here is my netlist (ngspice notation):
Rich (BB code):
1 :
2 : .global gnd
4 : .model 1n4007 d(is=76.9p rs=42.0m bv=1.00k ibv=5.00u cjo=26.5p m=0.333 n=1.45 tt=4.32u)
6 : c1 2 0 1000p
7 : d1 1 2 1n4007
8 : c2 4 1 1000p
9 : d2 0 1 1n4007
10 : v1 4 0 sin(0 5 1k)
12 : .end
My question concerns the current through node 1. I plotted that and zoomed in to find that it is a triangle wave, 10uA peak, at about 50KHz.
Hmm. I'm thinking maybe the current is leakage from the diodes? But I can't explain the shape or frequency. Can someone tell me where that current is coming from and why that shape and frequency?
I'm new to Spice, so maybe I did something wrong?
Thanks,
Keith Ostertag
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