Re: L297/L298 board concern

Hi Gary,
I havn't used the L297/L298 set, but the circuit inside them is
fairly common. I would suspect the Vref may be set to high so as to
not trip the comparators at the currect current (too high), or the
Rsenses may be the wrong size( too small in value). Both of these
issues could cause overheating by 'tripping' at higher than expected
current limits. Liberal amounts or heatsink grease is required for
bridging the surfaces of the heat tab to the heat sink. Without it,
there is impedence to heat flow between the two. 2amps
at 24v is 48Watts, so put your hand on a 48watt light bulb for a
rough analogy( the bulb will probably run cooler I think). Anyone
else have ideas?
-Lee

--- In CAD_CAM_EDM_DRO@y..., "stirlinguy" <Gary.Rose@c...> wrote:
> Guys,
>
> I have a L297/L298 board that seems to be getting REAL hot. It's
> basically just the circuit from the L297 datasheet. A friend of