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Next: 2.3.3.8 Voltage Controlled Current Up: 2.3.3 Devices Previous: 2.3.3.6 Current Source

2.3.3.7 Voltage Source

The constitutive relation for an ideal voltage source is given as V = V0(t). The voltage can be arbitrarily time-dependent and several common curve shapes have been implemented. However, no dependence on solution variables is allowed as this would result in a voltage or current controlled source (see Section 2.3.3.10 and Section 2.3.3.11). The stamp is given as
yx, y $ \varphi_{1}^{}$ $ \varphi_{2}^{}$ I f
n1     -1 I
n2     1 - I
I 1 -1   V0 - V
Again, the sign of the current is different as compared to the passive elements as it is defined to flow out of the source. Generalizing the branch relation to V = V0(t) - I . R, that is to a voltage source with series resistance, gives the following stamp
yx, y $ \varphi_{1}^{}$ $ \varphi_{2}^{}$ I f
n1     -1 I
n2     1 - I
I 1 -1 R V0 - V
Eliminating the current I results in the stamp for the current source with shunt resistance and corresponds to a Norton-Thevenin transformation of the source. For V0 = 0 one gets the stamp of the linear resistor.


next up previous contents
Next: 2.3.3.8 Voltage Controlled Current Up: 2.3.3 Devices Previous: 2.3.3.6 Current Source
Tibor Grasser
1999-05-31