[sdiy] Diode/Led/Gate out question

[Happy Harry]

It might work...  If you drive the anode of the LED from the
counter output (active high) and use one combination Pull down-
current limiting resistor for the LED... you would get gates
that are or'd together. I presume you must have a toggle switch
before this to turn off both the gate and the LED.

Note that most LED specift only a 5V or so reverse breakdown...
which you may violate depending on your supply voltage.

There is also a 2V (or so) forward drop that you must be willing
to give up (+12V supply = +10V gate... OK?)

The forward drop will be poorly matched... maybe vary a 1/2 volt or
so from LED to LED ??? (maybe not this bad if they are from the same
lot...)

My .02

H^) harry


>From: Peter Grenader <pgrenader at mksound.com>
>To: <synth-diy at dropmix.xs4all.nl>
>Subject: [sdiy] Diode/Led/Gate out question
>Date: Mon, 15 Apr 2002 05:28:37 -0600
>
>Guys/Gals,
>
>
>I'm just about to finish this sequencer I've been working on for the last
>week.  I'm at the 'wire all those pots and jacks to the PCBAs' stage.  I
>have a quesion for you guys which would a save me from wiring yet another 9
>pin Molex connector, of which there are already 5 ( I have a lot going on 
>on
>the faceplate):
>
>I need the outputs of the counter to do three things:  1) create the 
>voltage
>for the step pots 2) step gate outputs and 3) step LEDS.  I have the output
>of the counter coming to the faceplate in two ways: A) straight from the
>counter itself and B) counter outs routed throuh a non-inverting buffer 
>just
>in case i need more 'umph'.  I figured I would wait until I start playing
>with it to see which needs to go where.
>
>I was planning on just running the outputs of the counter (either buffered
>or not) through 1n4148's to create the gate outs. But I also them going to
>eight more diodes, thr step LEDs.  Could I take the gate outs from them
>instead? From (after) the LEDs?  will that suffice my needs?  In the
>billlion or so sequencer schemo's i
>ve seen I've never seen it done like this,  but I am curious if it would
>work.
>
>let me know and thanks.
>
>Peter
>




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