Look at the datasheet of the chip from the manufacturer you are
purchasing from.  I could be imagining things, but I recall that they
placed matching  resistors in the outputs (in the silicon) specifically
so they could be paralleled, and indeed, the data sheet had some
application circuits that showed just this functionality.

But perhaps it was only...

a dream...

(cue blissfull music and fadeout)

-Adam

Robin.Bussell@AXA-SUNLIFE.CO.UK wrote:

>Hi Folks,
>               from an EE point of view (without looking at mechanical
>production issues)
>is there anything drastically wrong with piggybacking a couple of ULN2003A to
>produce
>a driver array with better current rating than a single one?
>I'd expect there to be some thermal issues with the bottom chip when pushing
>things to the
>limit and so wouldn't expect to get 2x the normal current rating but maybe 1.5X
>safely?
>
>Just mulling over an idea for a low volume future project that won't be
>controlling
>any life or death situations, it's a scoreboard using electromechanical digits
>(ok so some
>might class that as life or death :)  ) where the larger sizes need a bit more
>current than
>a 2003 can comfortably sink.
>
>
>Cheers,
>            Robin.
>
>
>
>
>
>
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