1.8V opamps <15c/channel?

Since I roll-my-own I don't follow the "jelly bean" component market too closely, but I'd think there'd by rail-to-rail CMOS OpAmps available for 1.8V by now.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
               The harder I work the luckier I get.

They're probably still squeezing the market for the high-value stuff. It seems to take 5-10 years for the prices on that sort of thing to really settle to commodity levels.

If you are doing it all the time why not just keep that schematic page around and use it whenever you need to? Or do you build a different amp each time to meet the requirements du jour?

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

There are, but maybe not as cheep as Joerg wants. The LMV301 and AD8515 are both 28 cents apiece for singles, the biolar input RRIO LMV934 is 0.60 for 4 channels, which isn't too bad (0.15/channel).

Best regards, Spehro Pefhany

--
"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Hello Jim,

There are, even down to a volt. But the prices have remained too high.

Regards, Joerg

Hello Tim,

It seems to take longer than that on the CMOS opamp front. Thing is, most of the double-AA cells designs aren't high-value at all.

It's the du jour thing and this time it's a lowpass chain. All in my head, no need for schematics. But it would require a whole lot of discretes and the cheaper transistor varieties don't come smaller than SOT23.

Then there is the trick of using logic inverters as amps. However, with a couple of AA cells even 74HC becomes iffy towards the end of battery life. And at slightly above 3V for a fresh set of batteries their quiescent is a bit high.

Regards, Joerg

Hello Spehro,

The 934 is usually a little higher. The dual version 932 can be had for around 35c. Borderline ok but not quite there yet.

I wonder if there is anything similar from Asia.

Regards, Joerg

Stop doing cheap-ass projects ?:-)

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

| 1962 | The harder I work the luckier I get.

[snip] [snip]

Can't you make crufty Sallen-Key filters with just one transistor ?:-)

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

| 1962 | The harder I work the luckier I get.

"Joerg" schreef in bericht news:VjtEf.29366$ snipped-for-privacy@newssvr13.news.prodigy.com...

Perhaps because they don't want to go belly-up so that you can buy from them next year as well. A healthy business sense, I'd say ;)

--
Thanks, Frank.
(remove \'q\' and \'.invalid\' when replying by email)

Hello Jim,

Believe it or not they can be fun. After all, aren't most of your chips similar? At least the chips I was involved in were for disposable products, made in bulk quantities.

Some projects can be transferred to chips later but on this one that'll be a stretch. It needs 16bit math horsepower and a 16bit ADC while just nibbling on the battery at a few mA.

Regards, Joerg

Hello Frank,

We can buy the LM324 for around 10c a pop for many years and they didn't go belly up from that. What makes a LV opamp so much more expensive?

Keeping prices high in anticipation that the market will bear it can backfire. For my designs I can only say that this happens a lot. Many times there was that perfect chip but I opted for a discrete solution based on cost. Nice AGC amp but I went the PIN diode route. Great S/H chip but I went the xfmr/diode pair route. And so on, you name it. That's lots of missed sales. Sometimes this isn't understood by semi mfgs executives. Once a certain design is released it takes a major earth shattering event to change it.

A classical example was the switched capacitor filter. I used them in one design but that was more based on a client's wish. Never again. Now appear to be more or less gone from a biz point of view.

Regards, Joerg

Hello Jim,

Sure, but I'd need a lot of these. Plus some gain. This afternoon I'll have to do framing (ripping with a Skil saw, yech...) but tomorrow I'll probably square off an LM932 against a bunch of discretes. I have a hunch that the 932 will end up on the bench again.

Regards, Joerg

"Joerg" schreef in bericht news:TcvEf.707$ snipped-for-privacy@newssvr27.news.prodigy.net...

No, because they produce millions of that one.

Marketing, to prevent too many people using it, as that would endanger the cheap mass production of the LM324.

No it doesn't backfire. Selling everything for peanuts would; no control over what customers buy. Production runs would be smaller and smaller. Less profit, less money left to do research and develop new chips. New chips that you can afford, if not today, perhaps tomorrow or next year.

[snip]

--
Thanks, Frank.
(remove \'q\' and \'.invalid\' when replying by email)

They may be trying to say that we'd rather make more profitable components with our limited resources (aka process facilities).

When sales drop enough they'll announce a last-time-buy.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
               The harder I work the luckier I get.

National seems to have increased the budgetary pricing for the LM324 on their website- it's now $0.32 in 1K, believe it or not. A few years ago they said they were going to try not to make as many 20-cent commodity parts, IIRC. TI lists it at 0.16, which is still way higher than typical distributor pricing (more like 0.10, from the lowest cost supplier- ST). I guess if they can make as much off of 100,000 obscure backlight driver chips as 10,000,000 LM324s they may as well jack up the price of the op-amps and let the chips fall where they may.

Best regards, Spehro Pefhany

--
"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Hi Joerg, I'm confused, one minute you talk about high end "billion $ law suits"medical widgets and then how many cheap opamps can I get for

5cents.

Hope they are different projects.

Back to my mechanical 440Hz tuning fork that is GPS locked...my muso mate has perfect pitch.

martin

Hello Martin,

They are, this one is consumer. But even in medical I am often involved in disposable devices where every cent counts.

Regards, Joerg

Hello Frank,

They could do the same with the LMV series if the pricing was right.

Not quite. You cannot use the LM324 at all in devices that are 3V battery powered. Which is a lot of devices these days.

Runs would be smaller? They would be tremendously larger if they priced them right.

There is an old saying in America: "If you don't take care of your customers requirements, someone else will". All it takes is someone in Asia to pick it up. Hasn't happened yet obviously, but will. Until then I'll just stick with transistors.

Regards, Joerg

Hello Spehro,

Then the chips fall elsewhere. This would be like Volkswagen deciding to stop making Golfs. They'd be eaten alive by Toyota.

Even Digikey still has the LM324 (from ONSemi) for $0.112/2500qty as of today.

As to those driver chips I had an experience there as well. Not quite for a CCFL but a HV app. Nobody would budge in PWM chip pricing so I threw it all out the door and went discrete. That client is still as happy as a fish in the water, it's as cheap as it can get. I did get a few calls from the chip reps later, wanting to talk some more. Too late.

Regards, Joerg