Re: [CAD_CAM_EDM_DRO] Home build CNC

On Mon, 29 Apr 2002 10:46:17 -0700 (PDT), you wrote:

>>I'm still looking for help on the H-Bridge design :(
>>
>>If anyone can help, or has any suggestions please contact me.

>I dimly recal it's being mentioned, but not the details. What exactly are you
>having a problem with, vis a' vis, H bridges? Theoretically you can make an H
>bridge out of almost anything, even relays, though you might need a little
>superhero help from, "Cap'n Diode", to lock out relay ringing.....:-)

I have a H-bridge and a working L297 side, It's connecting the two
together that's the problem. The schematic as shown on my page, will
work, so I'm told, but will blow the L297 if the motor supply voltage
exceeds 5V.

It may just be simple matter of adding a 5V zenners to limit supply
between pins 4,6,7 & 9 on the L297 & the bridge. I'm not sure about
pins 13 & 14 (sense) and 5 & 8 (inhi) either but think maybe those
connections are OK?


Steve Blackmore
--
Pilot Consultancy Limited ***** Computer Consultants
Telephone 01744 752256 Mobile 07831 768478
Email: steve@... WWW: http://www.pilotltd.net