Re: [CAD_CAM_EDM_DRO] Parallel Port/Relay Problems... more

JanRwl@... wrote:

>
>Good "everyday" examples are the ULN-2003. Seven "transistors" in a 16-pin
>DIP (same as an "IC"). Each can sink up to half an amp. Also contains
>"anti-backlash diodes" for protecting transistors if driving solenoids, etc.
> There are also some "75nn series" mini-DIP's such as the 75477, which can
>buffer the parallel-port outputs for driving small relays.
>

The 75468N is the equavalent device to the the ULN-2003 (I think).
One other nice feature is that you can parallel sections
if you need more current than one section can provide. I have done this
in my conversion where I have a dozen or so solenoid
operated air valves on my mill. I used a bunch more single sections to
drive relays, etc. Nice little devices...
Larry....