0195136047.pdf

170 TIME-DEPENDENT CIRCUIT ANALYSIS

VS1010

L1210MHIC= 0, INITIAL CURRENT IS ZERO

R23100

C301UFIC=0; INITIAL VOLTAGE IS ZERO

* TRANSIENT ANALYSIS REQUEST

• TRAN 0.02 MS IMS 0 0.02 MS UIC


• PROBE


• END
  A plot ofvC(t)is shown in Figure E3.5.1(c).

Steady-State Sinusoidal Analysis with PSpice

PSpice can easily solve steady-state ac circuits for currents and voltages. Ac voltage sources,

which must begin with the letter V, are specified by statements of the form

VNAME N+ N− AC VPEAK PHASE

where VNAME is the name of the voltage source, N+is the node number of the positive reference,

N−is the node number of the negative reference, AC indicates that this is an ac source, VPEAK

is the peak value of the voltage, and PHASE is the phase angle of the source in degrees. Current

sources, which must begin with the letter I, are specified in a similar manner, with the reference

direction for the current source pointing from the first node number given in the statement to the

second node number.

The ac analysis request is made with a statement of the form

• AC LIN NPOINTS STARTFREQ STOPFREQ
  where•AC designates a request for frequency analysis, LIN defines a linear frequency sweep
  with NPOINTS specifying the number of points in the sweep starting at the STARTFREQ and
  finishing at the STOPFREQ. For example, to carry out a steady-state ac analysis for a frequency
  of 60 Hz, the analysis request would be


• ACLIN16060
  Let us present an illustrative example.

EXAMPLE E3.5.2

Use PSpice to solve for the amplitude and phase of the current and the voltage across the inductor

in the circuit shown in Figure E3.5.2(a).

Solution

The program is as follows:

* THE CIRCUIT DIAGRAM SUITABLE FOR ANALYSIS IS GIVEN IN

FIGURE E3.5.2(b)

VS10AC10030

R 1 2 100

L 2 3 0.3 H

C 3040UF