Cheap but good op amps

LM358A has a max offset of 3 mV, ballpark 10 cents.

John

Thanks.

Such an obvious answer and I missed it.

At 25C. Over the full temp range it says 5mV max.

But I love cheap.

Jon

Three or four cents per opamp section is sort of amazing.

John

Yeah. Now that I know they are THAT CHEAP, I'm going to add a few thousand to my box. That and some TL082's, I suppose. Unless you know some other very cheap, pA level bias current FET input thingies to look at!!

Jon

TL051, TL052?

How about the 4558? Better offset voltage, offset current, and slew rate specs than the LM358, Newark has them for 13 cents in SOIC in quantities greater than 500:

Definitely nicer on the offset voltage and a bit better on the offset current. Now I just need to find them real cheap in TL051CP in 1000 qty.

Thanks, Jon

Doesn't meet the

Limited input common mode range compared to LM358.

Grant.

We're paying 18 cents for LF347s. Quads!

John

Which disty and in what qty?

thanks, Jon

yep, no good on a single rail.

LF353 is what I have here -- Digikey lists them for as little as $.18, I dunno if that's cheap enough for you.

--

Tim Wescott
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Since I give these things away to students and just about anyone showing an interest, in qty enough for playing around and screwing up, I like to keep the purchases within about $200 per buy but I like to get about 1000 for the trouble, or better. This makes twenty cents my rough limit for anything I get, though I tend to shoot for "as low as possible" and will buy older, lead-based stuff to get it. Usually looking for DIP in ICs, SOIC acceptable. One of my "best" buys was

26000 OnSemi PN2222A devices for $0.0028 each. I'd like to find a PNP offered near that price and qty.

I'm really cheap. But that's because I don't want to have any feelings stopping me when someone "seems" interested, but I can't be sure and just want to remove a barrier for them to get started on the mere chance that someday they MIGHT use the parts. You never know with a high school student, for example. And I don't want to hold back just because I'm worried about my costs.

Jon

I buy in tens or hundreds rather than thousands, and I can't cite US prices except for those at the well-known online shops. These are Indian prices of devices I use as regular workhorses in approximate dollar equivalents: PNP - BC557B (0.1A) - $0.0016 PNP - BC327 (0.8A) - $0.0022 NPN -BC547B (0.1A) - $0.0016 NPN - BC337 (0.8A) - $0.0022

I used plenty of PN2222A and PN2907A in the past but have switched to BC337/327 where I need higher current levels than the BC547/557 types can cope with. These European BC types all have higher gain, higher Vceo and lower Vce(sat).

Excellent. Now if I can just find a supplier that will ship to a US address at those prices!!! You looking to be a disty any time soon?? ;)

Jon

I've used all of the types mentioned so far. It will be hard to beat the LM358/A in VFM, or the quad version LM324. My other workhorses: TL072, TL074

4558 (dual) and 4136 (quad) for lower noise 5532 (dual) and 5534 (single) for even lower noise but still at low cost

A big OOPS!! Remove a zero after the decimal in those prices!! I was hasty and was misled by the two zeroes in your price. So my prices are far from excellent compared to yours, but they are for small quantities. Bulk prices should be better, but so far I've never had reason to find out.