A few days ago Ludwik Kowalski was asking about a program called
Electronics Work Bench.
I have version 5.0 of this program and can make a report as to my
experience with it.
It is extremely easy to use for setting up circuits. Unlike earlier
programs, nodes are represented entirely as circuit connections on the
very viewable schematic which the programmer builds, one component at a
time.
The drawing of the schematic is very intuitive and convenient. It is
very flexible and the only problem I had was learning how to work with
its flexibility. Experience quickly lead to a comfortable feel.
After the schematic is drawn, a simulated switch is clicked on which
starts the simulation by applying simulated power to your simulated
circuit which is represented by the schematic drawing.
There is an arsenal of power supplies, measuring and signal generation
equipment which can be "dragged" into the schematic area and the leads
hooked up exactly like you would if it was a real circuit. The
oscilloscope has many great features as does most of the other test
equipment. Quantities of individual volt meters and ammeters can be
connected and disconnected into any part of the circuit at any time
that you want to. Each meter can be adjusted on a pop-up menu for its
voltage or current range etc.
Every component also has a pop-up menu by which its value can be changed
at any time. Each component has a way to insert a defect into it. For
example, capacitors can be made to be leaky etc.
The entire synthesizing of a circuit is done by equations that represent
each components and which are linked together in such a way that the
circuit is represented by a Huge formulae that is continuously being
solved while the circuit is running. I have a 300 MHZ machine and
things seem to move along pretty well, but I would sure hate to run the
same program on a 10 MHZ machine.
Problems that I have run into.
1. I got the program to demonstrate problem solutions to youths. We
start youths out on lights and switches. While the version I have works
fine on complicated, multi-element, electronic filter circuits, it is
flaky when used with a circuit that consist of only one switch, one
power supply and one incandescent light bulb.
2. In modeling a diode, the intrinsic stand off voltage is one of the
parameters. As the input to a transistor is just such a diode, I don't
under stand why an amplifier using a bipolar transistor neglects this
parameter in circuit simulation. I have tried to build timing circuits
on several occasions where the base to emitter intrinsic stand off
parameter is part of the real circuit, and the simulations don't work
out quite right.
3. There is a wide selection of active devices to choose from, but the
list of transistors and ICs contain many that I have never heard of,
and though large in quantity, they seem to represent a narrow range of
actual classes to choose from. There is a way of downloading many
additional devices from a master list but I have not mastered the
complications of this procedure at this time.
4. Be aware that there are two versions of this program. one is much
more costly and has analyzing capability that my program doesn't have.
After knowing what to look for, it is fairly clear that this capability
is not in the inexpensive version, but by not knowing this before hand
the advertizing might seem a little misleading.
I called the factory about problems one and two and got a very nice guy
who said he was glad to hear of these problems and that the company had
just upgraded their product, and since I had not had mine but for about
a month, he would send me an updated copy. This was the last time that
I have heard from them, I have never gotten the upgraded version and
have not gotten any feedback or suggestions. It is my fault for not
following up however.
Electronic Work Bench has a web page at:
< http://www.interactiv.com/ >
And has a free download demonstration program that will let you build
enough limited circuits to get a feel for what it is like.
I have not used the digital circuit simulation features at this time.
Digital circuits are so easy to design that they don't usually need
simulation.
Over all I have had a great time playing with this program. It is fun
to build and trim out complicated analog circuits in an hour or two that
would take days to do if real parts had to be mounted on real boards. I
just wish that I had a little more confidence in the results.