This ought to be easy, so I'm embarrased. But, can anyone clear up how to use a current-controlled current source (part "F") in PSpice 9.1? To get it to measure the controlling current, I have to connect the two measuring terminals with a resistor in between them. However, it then looks like PSpice treats the path through the CCCS as a short-circuit. So, I guess I have to attach a resistor someplace in that path. But, what value resistor? The same as the one between the two connection points? Or, do I have to come up with a combination of two parrallel resistors with an equivalent resistance equal to the resistance originally between the two connection points?
PSpice 9.1 Current Controlled Current Source (F)
Jan 16, 2006
2 Replies
No resistor needed in the sensing path... it's a zero-volt voltage source.
The _output_ is a current source (selectable gain), but you need to load it with something to avoid floating node issues.
...Jim Thompson
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It\'s what you learn after you know it all that counts.
Dave, The inputs don't actually exist as a pin connection in 9.1, they are just sense points. What you need the resistor for is two-fold. First, it provides a second connection point, so you don't get an unconnected pin warning. Second, if the other end is grounded, it provides a DC path to ground to prevent floating nodes. Usually, a very high value resistor prevents any loading effects.
Charlie
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