David Meiklejohn wrote:
> So - imagine there was no driver there.  Each of the 887's "high-side"
> outputs, labeled D0-7 and A0-3, is connected to a single row of 7
> LEDs. Current will only be sunk from one of these at a time, as each
> column on PORTC is pulled low, so each of the high-side outputs is
> only ever driving as single LED at a time.

Right, but look at the current.  Even ignoring that the OP wanted 25mA thru
the LEDs instead of 10mA or less, consider the time each LED is on.  To get
a average current of 10mA requires about 10x that during the brief on time.


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