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Topic: H Bridge Chip Suggestions (Read 1 time) previous topic - next topic

dezguy

I've been working on a robot project, and I'd like to build a custom PCB which combines a avr microcontroller, power supply, h-bridge and sensor circuits. My attempt is partially to learn about making my own PCB, but also I'd like to make a nice clean robot without a bunch of wires hanging off it.

So far nothing has been too overwhelming, but I came across quite a few h-bridge chips in my research and I wondered if there was some guidance from the group on some of the options.

My needs are pretty basic. Two 0.15 amp 3v motors, I'd like to operate fwd/reverse with PWM speed control.

A few chips I've looked at:

L293D
754410
L298
LMD18200

Does anybody have experience with these chips and how did it work for you?

I have a couple of 298s in my stock, but I don't have fast recovery diodes. But, overall it seems a bit overkill for my needs.

If you need further details just let me know.

Many thanks,
Mike

CrossRoads

I was just reading the L293D datasheet for someone else, looks like it'd do the trick for those motors.
Built in diodes too.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

zoomkat

Be aware that these types of chips may have a voltage drop across them that might be significant in the 3v range. 4.5v might be needed to get full performance from the 3v motors.
Google forum search: Use Google Advanced Search and use Http://forum.arduino.cc/index in the "site or domain:" box.

dezguy


Be aware that these types of chips may have a voltage drop across them that might be significant in the 3v range. 4.5v might be needed to get full performance from the 3v motors.


I was planning on a 9V power supply (AA batteries) for the entire board, so I'm thinking I should be ok?

dezguy

#4
Feb 26, 2011, 04:48 am Last Edit: Feb 26, 2011, 05:53 am by dezguy Reason: 1
I'm wondering, did I get the hook ups on the 293D correct (see circuit attachment)?

Do they make a dual inverter? Or do I need to use a hex, and waste the empty pins?

CrossRoads

Sure, you can get a dual inverter - its called 2 transistors :)

But if you're not doing much else, why not just use 2 more pins?
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

dezguy

Yeah that looks much simpler. :)

Do you mean, use two pins on the mu?

CrossRoads

Yes, 6 pins total from the arduino. 1A ,2A, 1-2Enable, 3A, 4A, 3-4Enable.

Transistor and 2 resistors about as simple as it gets for an inverter. I used that to invert a TTL level serial stream so the 328 UART would read it correctly.

You could try this sn74lvc2gu04 from TI if you don't mind surface mount
http://focus.ti.com/lit/ds/symlink/sn74lvc2gu04.pdf
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

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