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A-SIM for the HP-42S

Analog circuit simulator - Simulates circuits with: resistors, capacitors, coils, op-amps, and voltage sources.

Input:

An N*4 matrix called: "CIR" with the circuit description. Each line in the matrix contains one component.

Column 1 in the matrix indicates the type of component (1 to 5), column 2, 3, 4 indicates the value and / or the node numbers of the component.

 Resistor: 1, value, node1, node2 Coil: 2, value, node1, node2 Capacitor: 3, value, node1, node2 Op-amp: 4, node-output, node-input+, node-input- Voltage source: 5, value, output+, output-

The order of the components in the input matrix is: resistors, coils, capacitors, op-amps, voltage sources.

The Output- of all the op-amps are connected to node 0.

Usage:

After starting A-sim the following menu appears:

• U_IN:
There is always a voltage source connected to node 0 and node 1, the value of this source is U_IN.

• W:
w is the frequency of the simulation. This is 2*pi*f [rad/sec]
When using coils and / or capacitors the value of w has to be greater than 0.
• GAIN:
This is the gain of all the op-amps in the circuit.

Fill in all the values that are necessary, and press R/S.
The result is an Nx1 matrix.

On row 1 the voltage of node 1 is displayed, on row 2 the voltage of node 2 is displayed, and so on.
If there are coils and / or capacitors in the circuit, the result is a complex matrix.

If there are extra voltage sources in the circuit, then for each voltage source an extra row in the output is added which contain unusable data.

Known bugs / limitations:

It is not allowed for an op-amp output to be the highest node number in the circuit.

Example 1:

Input matrix ("CIR"):

 1 100 1 2 1 200 2 0 1 300 3 4 1 400 4 0 1 500 3 5 1 600 5 0 1 700 6 7 1 800 7 0 1 900 6 8 1 1000 8 9 4 3 2 4 4 6 5 7 5 20 9 0

U_IN: 10V,

W: 0

Gain: 1000000

Result matrix:

 10 6.6667 11.6666 6.6667 6.3636 11.9318 6.3636 15.7536 20 0.0045

Node 1: 10V

Node 2: 6.6667 V

And so on.

Example 2:

Input matrix ("CIR"):

 1 1000 1 2 3 1e-09 2 0

U_IN: 10V,

W: 628318.5307 (100000 kHz * 2 * Pi)

Gain: 0

Result matrix:

 10.00 i 0.00 7.1696 i –4.5048

Node 1: 10V

Node 2: 7.1696 i –4.5048V

Revision history:
9th of November 2004 - Replaced line 68 RCLx "J" with  68 -1, 69 SQRT, 70 x

Binary files for emulators:
Raw binary: asim.raw  Binary for HP-42X: asim.42x (HP-48) asim49.42x (HP-49)

Generated by 42s2html - 09 November 2004, 21:19