Re: [CAD_CAM_EDM_DRO] enable inputs on l297 / 298

Alan,
For the L298 and similar devices, CPU's, etc it is common practice to use
a power up/monitor device. Yes an RC will work, but there are several devices
made for this and also provide protection if the supply should droop.
Delays around 300ms.
The Dallas Semiconductor DS1233 is one. They are 3 terminal packages in
various styles and go by various names.
RichD

alanhunt2001 wrote:

>
> I have another problem with my l297/298 controller.
> When I turn on the controller with the enable input high, the
> output current goes sky high (or would if my temporariry bench power
> supply did not have a current limiter)
> I have to ensure the enable is kept low untill after the power is
> turned on. The l298 data sheets does mention that its enable inputs
> have to be kept low on power on.
> Funnily enough I had no problem with this when I supplied both 5v
> and 30v from the same dual supply and not as I do now w-with the 5v
> derived from the 30v via an on board regulator.
> I'm thinking that an RC network will produce an automatic delay in
> raising the enable from low to high on powering up but like to check
> if anyone else has had, and solved this problem first.
>
> thanks in advance
>
> Alan