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H-Bridge Circuit Help Answered


I have an assignment to build an H-bridge circuit to control the direction of a motor with two buttons. The only materials I can use are depicted in the image; only three resistors, a battery pack, two button switches and an L283D chip. Based on the template given to me, I constructed the circuit as shown in the picture but it does not work. It looks very messy and I'm sure there's an easier way, but I just want to get it working first. If anyone knows what I'm doing wrong here I'd appreciate it.


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Jack A Lopez
Jack A Lopez

2 years ago

I think your H-bridge IC is a L293D. Not L283D.

I am kind of wondering about a few other things.

Did you find that L293D H-bridge in the "Core" parts box, of your copy of Fritzing? Or did you have to import it somehow? Also what version of Fritzing are you using?

Coincidentally, I think the IC that I picked out of the "Core" box, has the same pin outs as L293D.

Another thing I am wondering about is, what program you are using to simulate this circuit?

I mean, you're not actually building this thing on a real physical breadboard, are you?

Regarding what DU35m says about the "good guys" refusing to help with homework assignments, I think I must be one of the "bad guys", because I'll help anyone. I mean, if I feel like it.

Some pictures are attached. By the way, I am not totally certain my implementation is free from errors, since I have not tested it. But I am showing you my best guess for the way to do this, with the parts given.


2 years ago

There is no real help given here by the "good guys" when it comes to homework or assignments.
Their purpose is that student learns and manages with the task at hand.
So I will give you some hints that should allow you figure out what is wrong.
Start by checking the datasheet for your IC.
You will find several from different manufacturers.
Some will contain detailed information on how to do the basic setup, including what parts are required.
Through that you will find the missing parts in your circuit and also see why the motor should not be connected directly like you did.
Keep in mind the limitations and voltage requirements of the chip as stated in the datasheet ;)
Same for selecting a suitable motor.
You don't want a motor that needs more voltage or current than what you can provide ;)