_[sdiy]_ICL8038 worst ic off all time!

[Magnus Danielson]

From: Scott Gravenhorst <music.maker at gte.net>
Subject: Re:_[sdiy]_ICL8038 worst ic off all time!
Date: Mon, 08 Mar 2004 16:38:55 -0700
Message-ID: <200403090038.i290ctg11008 at linux6.lan>

> >> >There should be a list of "worst-IC-designs-of-all-time" it would 
> >> >also be nice with a list of the most "neat" IC design of all time to!
> >> >In the first list i would definitively put the 8038 and a bunch of
> >> >early FM chips! In the second list i would put the 555, the 4046.
> >> 
> >> 555, I agree, in fact, I'd put that on the "worst IC of all time" list.
> >> The 7555, however is fine.  I like the 4046 used as a PLL, I built a
> >> frequency multiplying module with one.  The VCO basically sucks by
> >> itself. 
> >
> >Hmm, i dont think the VCO sucks,as i remember, BJ showed once many years
> >ago that you could build a remakable advanced VCO out of a 4046 IC! Well,
> >at least a "very high frequency LFO" with sync and 4 quadrant modulation
> >on the square, if im not remebering completely wrong, thats not bad for
> >such a cheap and simple IC. Or one could use the HC version and do a
> >nice DC to 30Mhz function generator. I say forget about the 8038! 
> 
> Looking at the spec, a 4046 is rated at 1.3 MHz, the 74HC4046 version runs
> at max 17 MHz.  The VCO is fine, it's the current source that isn't very
> good.  Check the TI docs, it has a whole section on the technicals of
> the VCO.
> 
> I built up that circuit by Bjorn Nilsson(?) and couldn't
> get it to track a linear CV.

As I recall it, in the 4046 you have basically two inputs and one of them is
really a current input, so that's your entry into the world. I did exchange
emails with Björn Juhlin back then, and I don't recall exactly but I think I
helped him with that particular part (I might have just caused confusion, since
I was a little hasty to analyse things and made a few errors where he was
right as I recall it).

I haven't heard from Björn for several years now.

Cheers,
Magnus