any op-amp recommendations?

I'm wondering if that's a typo and you mean LF412?

I too have been on the lookout for an inexpensive general-purpose op-amp, but with higher input impedance than the 741.

Thanks,

Mark

Yes, sorry.

Right.

--
 Thanks,
    - Win

I've prototyped a lot of circuits with OPA134 in solderless breadboards; no problem. It's not really blazingly fast - good audio opamp but not the sort of thing that will get you in trouble.

However, it's rather expensive as a "jellybean" opamp. I usually prototype first with something cheaper, e.g. TL08x, and then plug in the OPAx134 at the end.

I'm getting ready to order some junk from Digikey. Can someone recommend good general purpose op-amps to stock for tinkering? I've been using the 741 just because I had a few laying around, but I know that better things exist. I've also got a couple of TL082s, but really haven't done much of anything with them yet. The 741 has worked ok (more or less) for me, but I want something with better gain at 40kHz (ultrasound tinkerings) and that can go much closer to the rails since I like to use 5V for power. Something that won't easily latch up would be nice too. I don't need anything really fancy, just something relatively inexpensive ($2 or so) and easy to use. BTW, I like to use solderless breadboards for prototyping.

For comparators I use the LM393, is that still a reasonable choice or should I stock up on something newer?

TIA

OPA134 for a traditional OP-AMP. Single version.Think of it as a really beefed up TLO81. Power bypass caps are necessary for high speed amps.

greg

In article , GregS wrote: [...]

I'd worry about the OPA134 in a solderless breadboard.

--
--
kensmith@rahul.net   forging knowledge

LM393 the best price/perfamance comparator ever made.

"Winfield Hill" wrote

Thanks. :-) Any recommendations for something in the 5V single supply arena?

"GregS" wrote

Thanks. :-) I looked at the datasheet and it seems like a real nice part especially for audiophile applications. Fast and really low distortion, but it sounds like it may be a bit wild for the breadboard.

Cool, I guess I'll stick with them then. :-)

I don't like getting into bed with an opamp with no schematic.

--
 Thanks,
    - Win

For 5 volt supply, I like the MCP6022-I/P, dual, rail to rail, 10 MHz GBW product (gain of about 250 at 40 kHz), made by Microchip, the people who make the PIC microprocessors. Digikey sells these for $1.80 each.

But a good, cheap jelly bean amplifier for low frequency use is the dual LM358. Works from the negative rail up to 1.5 volts below the positive rail. About $0.50 each.

I still use lots of those and the quad LM339, also.

"John Popelish" wrote

Way cool! I think I'll buy me a few. :-) The chip select feature is pretty nice and I like that cute Vref available on a couple of the sibling models. I couldn't find anything in the datasheet on how much of a drain the Vref added on the power supply, but with total quiescent current at about 1mA, who cares. ;-)

I'll look at the datasheet, but the microchip op-amp looks like it just might be the one. Thanks again.

or

LF412 ?

Odd choice. Hardly ever see it in commercial kit. Well, never actually.

TI's TL series of bifets would make more sense.

Graham

For rail to rail apps (in and out), I love the TI TLV237x family.

-- Andrew

I think it time to move to micropower op-amp and dispose +/-15V or

+/-12V (unless you really really need it). I work on +3.3V and +5V schematic with various rail to rail op-amp, the performance is pretty good nowaday, especially low noise just released by LT. It also easier to interface with digital circuit. I use ADR361 for voltage reference source as midway.

Good luck

Avoid Advance Linear Device...the op-amp range is really crap!

Thank you for mentioning them, they look like just the thing for my purposes (home hobbyist, low frequency analog stuff, such as photodectors and thermal measurements).

Mark

What do you mean by "range" and what do you mean by "crap"?

--
 Thanks,
    - Win