Re: trouble with logic counters

panfilero wrote:

.... snip ...
I'm powering the circuit with a 9 Volt battery, I'm splitting that in
half using a couple resistors (of equal value 10 Mohm) in series and
taking the voltage from one resisttor and using it as my high for the
counter. I've connected the pins in this way:

.... snip ...
12 Q2 - to a 1K resistor in series with an LED
13 Q1 - to a 1K resistor in series with an LED
14 Q0 - to a 1K resistor in series with an LED

That logic series, IIRC, uses 5 volt supplies. You are effectively
supplying 4.5 volts through a 5 M resistor, which won't run it. 1
uA draw will result in zero volts at Vcc. Get a 5 volt regulator
chip.

Also, where does the voltage to the LEDs come from? If the 9 volt
supply, you have probably already destroyed the chip. It the
alleged 4.5V thru 5 megs there is no power to run them, but you
probably haven't destroyed the chip.

Read up on Ohms Law. It's not hard.

--
Merry Christmas, Happy Hanukah, Happy New Year
Joyeux Noel, Bonne Annee.
Chuck F (cbfalconer at maineline dot net)
<http://cbfalconer.home.att.net>


.

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