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tehmoordar
05-25-2005, 12:01 AM
Hi,
Iam using robot atr ers from roguerobotics.com and with it I have motors who consume very high current like 5 amps if stalled
(item # 1205·at ·hobbyengineering.com) I have one H bridge and I want to controll the speed of the motors -- I am thinking about using PWMPAL but I am not sure how I will be able to connect the Hbridge with the PWMPAL. since Hbridge has three wires to for each motor. I also dont know whether this setup· will be able to handle 5 amp curret from my each motor.

Or any suggestion how should I controll the speed of my motor
Thanks

Beau Schwabe (Parallax)
05-25-2005, 09:17 AM
tehmoordar said...

...I have one H bridge...




tehmoordar said...

...since Hbridge has three wires to for each motor...




I'm confused.... Typically you use one H-bridge for each motor.

Some may disagree on my method, but I typically use an H-bridge to control
direction ONLY. To control speed I use a MOSFET or paralleled MOSFETS
that supply power to the H-Bridge which in turn supplies power to the motor.

The PWMPAL will work, but I wouldn't use it to drive the H-Bridge unless the
H-Bridge is capable of accepting a PWM signal... Some do and some do not.
...Instead I would use the PWMPAL to drive a MOSFET supplying power to an
H-Bridge.

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Beau Schwabe - Mask Designer III

National Semiconductor Corporation (http://www.national.com/)
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tehmoordar
05-25-2005, 11:13 PM
HI,

I have LCHB 100 ( H Bridge)which I got with my robot ATR ERS from roguerobotics.com and I was initially using micro dual motor controller from pololu.com· but since my motors are high on current so I am looking for new method to control speed of my motors.

Now being novice give some example and link as how to controll motors speed using BS2, MOSFET and Hbridge.

How to go about it and start it

Thanks

Beau Schwabe (Parallax)
05-26-2005, 12:30 PM
The documentation for the PWMPAL has an example of using a MOSFET to control a motor.
Instead of a motor in this circuit use an H-Bridge.

PWMPAL (http://www.parallax.com/detail.asp?product_id=28020)

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
------------------------------------------------------------------------------------
Beau Schwabe - Mask Designer III

National Semiconductor Corporation (http://www.national.com/)
Latest Company News (http://www.national.com/news/)
(Communication Interface Division)
500 Pinnacle Court, Suite 525
Mail Stop GA1
Norcross,GA 30071
-------------------------------------------------------------------------------------