Re: High voltage protection for a breakout board.

Chris,

The new board has the option (jumper) of using pins 2-9 for input. I
will gladly relpace it. Please allow till the end on next week for
the stock to be available.

Arturo
--- In CAD_CAM_EDM_DRO@yahoogroups.com, "lcdpublishing"
<lcdpublishing@y...> wrote:

> Hi Arturo,
>
> I don't know enough about electronics to say one way or the other
> with regards to your direct question. However, there is something
> that I think should be considered.
>
> I am adding your breakout board to my CNC system which uses the
> Hobby CNC board on LPT1. Your board is going on LPT2 to protect

the

> computer from the various experiments I plan on doing. The MACH3
> software allows for pins 2-8 to be either inputs or outputs. As
> outputs, your current board is good, however, if I want to use

those

> pins as inputs, I believe there is a problem with the isolation.
> Perhaps you should consider running two circuits for those pins,
> making them either inputs (isolated) or outputs (Buffered).
>
> Just a thought.
>
> Chris
>
>
>
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Arturo E. Duncan"
> <aduncan@c...> wrote:
> > Group,
> >
> > I have been working a design for a new breakout board for general
> use
> > in cnc applications. The new design is based on the SN74LV245AT
> IC,
> > wicth acts as a bi-directional buffer and has ESD (Electro Static
> > Discharge) protection for up to 2000V. I have been hoping to
> > eliminate the opto-isolators with the use of these IC, and will
> > greatly reduce the number of parts and simply assemble, thus
> enabling
> > the possibility to reduce the cost of the final product.
> >
> > I know for most interfacing applications this IC is a great
> buffering
> > device, but ¿would it be good enough protection from a possible
> > failure of a stepper driver?
> >
> > The datasheet for this IC can be found at :
> > http://www.cnc4pc.com/Tech_Docs/sn74lv245at.pdf
> >
> > Thanks,
> >
> > Arturo Duncan