Simple Schematic Drawing Software

[Gary Lecomte]

Feb 10, 2009 16:19:38 GMT -8 @kitbuilder said:

I am looking for a new software package for drawing schematics. I'm not in need of a PCB program at this time. I have looked at the big hitters, (PCB123, Express PCB, and others) but these do not have the features I am looking for.
So if you have a program you particular like, and would take the time to share your opinions and comments, I would appreciate it.

So what features are you wanting?

[rmeyn]

am looking for a new software package for drawing schematics. I'm not in need of a PCB program at this time. I have looked at the big hitters, (PCB123, Express PCB, and others) but these do not have the features I am looking for.
So if you have a program you particular like, and would take the time to share your opinions and comments, I would appreciate it.

The question I have is: Why just draw schematics? If you are designing I would use a simulator, for the many advantages it has. When you have a design in mind, it is relatively simple to convert it into a printed circuit board. Express PCB does this well and I have not found any shortcomings or features missing in it.
I have also used my copy of Pspice effectively for the same purpose
rmeyn

[Gary Lecomte]

Rmeyn, You have obviously never built any Critical type circuits.

I have yet to see PCB Software take into account Trace Widths as needed for high currents or where there are Very sensitive circuits, where two traces side by side, causes signals to interfere with each other.

And No PCB Progams take into account Ground Loops.
Besides a Good Program, you need the Understanding of what criteria is really important in a particular circuit.

These problems Require Good Knowledge of the designer.

I have 2 registered versions of Electronic Workbench.
Origionally cost about $800.00 each.
EWB-4 and EWB-5 and I have simulated many circuits in them also.

And Yes I can do up schematics in them and I can save or print them.
But the quality of printing them is not really very good.

All these programs I have seen, print lines as a "1 Bit in width", resulting in poor quality if you try to enlarge it. And most also Print in Color, which can add to more problems.

[rmeyn]

No I've had to calculate trace widths using algorithms that are available. Placement I've had to adjust in critical oscillator circuits.
I wasn't really emphasizing the printed circuit board aspect of the software. I just can't understand why anyone would just want to
"draw" schematics! Designing circuits to produce a schematic makes more sense to me.
rmeyn

[Gary Lecomte]

Rmeyn, I have a circuit I want you to simulate and give me your results for both current and voltages as shown.
Seperately, using each light bulb shown.



I wish to compare your results, with my simulation, as well as the real measurements of this circuit.

[rmeyn]

I will Gary. Any specs on those diodes?
rmeyn

[Gary Lecomte]

Feb 11, 2009 14:00:55 GMT -8 rmeyn said:

I will Gary. Any specs on those diodes?
rmeyn

1N4005's, But Not Critical for these measurements.

[Gary Lecomte]

Here is a Simulation of the Origional Watt-meter Circuit.
Done in the Professional Registered Version of "Electronic Workbench, 5.1"

The Actual Overall Current for the 500 Watt bulb is 4.6667 Amps and the uA meter should read 25 uA.
Neither read correct!

The Actual Overall Current for the 1000 Watt bulb is 8.8333 Amps and the uA meter should read 50 uA.
Overall Current reads correct, but not the uA reading

Both Voltage Readings are also WAY OFF.

Other than Changing Switch Positions to change loads, I Made NO Changes to the circuit.
Yet on the 500 watt load, it can't even correctly display the over all current.

Changing the Transistors to other types, such as two, 2N4123's, Also Screws up the Overall Current on both simulations.
Since the Load remains Constant, that Shouldn't occur.



Sorry, but I have Very Little Faith in Simuations.

But Simuations seem better for Digital circuits than Analogue ones.