Paging Master Pu..(RG)

[Davefx]

I couldn't resist the subject title,   :lol: .  I have  2 questions, which I'm 99.9 % sure you could answer. First, Mouser lists 3 different TL072 's in their listing.. TL072ACP (1.18)TL072CP (.94), and TL072BCP ($1.80). Do you know the difference between them? Myself being ever so cheap, I chose the .94 version, should I have?

 And 2nd,  Mouser also lists a charge pump chip that you didn't mention in your article.  It's a TC1044scoa, I saw the 1044 and read that it has a frequency boost and thought that it may be a new generic equivalent to the Maxim chip.  Just wanted to see if you could shed any light on this.

 Your thoughts and sermons are always greatfully appreciated.

  Grasshoppper... (Dave)

[R.G.]

When you can snatch the datasheet from my hand, then it is time for you to leave...  :wink:

The datasheet at www.ti.com says that for the TL072 series, "C" indicates the commercial temperature range of 0 to 70C. The "CP" parts have a maximum DC offset voltage of +/- 10mv, the "ACP" have an offset of +/- 6mv, the "BCP" part has an offset of 3mv max. This is a key indicator of the DC accuracy of the part - which has almost no bearing whatsoever on the AC performance we usually want in effects. Unless you're doing high accuracy servos or integrators, use the cheap ones.

I suspect that if you buy the 10mv parts, you might find that there will be no part any **better** than 7mv offset, because these are usually selected for higher performance. They cook a whole batch of them as good as they can make them, then select out the all the 3% parts for the more expensive "BCP" parts. Then they select the parts from 6mv to 3mv for the "ACP" parts, and the rest that pass at least 10mv are the "CP" parts. When they mark the packages, if they're selling all the "B" parts they can, all of those are gone from the distribution. But if they get few orders for "A" or "B" parts, they just mark all the parts as "CP" and ship them.

Anyway, use the CP's unless you're doing high DC accuracy stuff.

Notice that different manufacturers use the same suffix in different ways. The LM381A is a lower noise part than the LM381. The TL072A is a lower offset part than the TL072. The 2N3391A is a lower *gain* part than the 2N3391. You have to grab the datasheet to find out what the maker meant when they said "A" or "X" or whatever.

[Davefx]

Thanks RG...  Of course, if I would have THOUGHT FIRST , and went to the TI website, maybe you wouldn't have had to bother!  So therefore I'm going to attempt to compare the data sheets on the Maxim chip and that one in mouser, although I'm not engineer by any means, I will try to see if I can safely make an assumption whether I could use it in place of the Maxim...  Or just buy the Maxim, what the heck. I just never order from Digikey, but I may, or there's always good ole Steve at Smallbear..

Thanks again RG...  "It is time for me to leave"... :lol:

Dave