I need a compact sine wave generator (~5V) for a 2x2" circuit board. Around 5kHz.

I have used a few ICs for this in the past but they are obsoleted! Noise is an issue and my few op-amp designs have more EMI than a compact chip.

Anyone out there have a favorite that they have found to be fairly "quiet". Stability and accuracy not an issue here--

cheers
Fritz

 

Try XR-2206

 

Read up on the Bubba Oscillator, here. It can be built using a generic quad opamp. AFIK, the Exar chip is obsolete.

 

My fault for just digging around in my old files instead of searching the internet.

 

As of last month or so, XR chips were on eBay. I can't vouch for their quality.

 

A really "quiet" sine oscillator is a single transistor phase shift oscillator which runs linearly and has no crossover or current peak issues, and is easily small enough to fit on your PCB.

Since you said stability and accuracy (freq? waveform?) is not critical that should do the trick.

 

Read up on the Bubba Oscillator, here. It can be built using a generic quad opamp. AFIK, the Exar chip is obsolete.

For those that have to have one, here you go. Not cheap @ $7.50 ea.
About halfway down the page..
http://www.elexp.com/ics_10cn.htm

 

For those that have to have one, here you go. Not cheap @ $7.50 ea.
About halfway down the page..
http://www.elexp.com/ics_10cn.htm

EBay has them for only $3.29 with free shipping (2.30 in quantities of 10). Seller Tayda seems to have a US shipping point because I get their stuff in a few days. They also have a website Taydaelectronics.com but the have a $5 minimum and charge a buck for shipping. EBay is the better deal for one or two.

http://www.ebay.com/itm/XR-2206-XR2...111?pt=LH_DefaultDomain_0&hash=item4163c7e1df

 

Thanks for the replies. Jeessh-I thought there would be a lot of sine ICs out there these days but in fact searching the digikey database there are very few and none stocked. Unobtainium as we say! Mouser had their last three XR2206 in the solar system for $71/each! I can probably buy complete B&K func-gen for that price. In a few years couples will be getting sine ICs mounted into engagement rings (;->

No surprise some respondents just do it the old fashioned way and grow their own-more fun at least. At any rate i'll clean up my old design and meanwhile place an ebay order. BTW - The MAX038, also obsolete looks interesting-

cheers
Fritz

 

1. NE555 50% duty cycle 5Khz astable circuit → RC integrating circuit → bjt amplifier.
2. NE555 50% duty cycle 5Khz astable circuit → LC integrating circuit. (adjust the amplitude)

 

... Unobtainium as we say! Mouser had their last three XR2206 in the solar system for $71/each!
...

You have to know where to look. This surplus supplier has 24 in stock at $12 each;
http://www.rockby.com.au/SearchresSql_12.cfm?Searchkey=XR2206

But as I said before in post #6 why bother with a chip? You can use a 20 cent transistor and a few caps and get a much more "quiet" sine oscillator than any chip.

 

But as I said before in post #6 why bother with a chip? You can use a 20 cent transistor and a few caps and get a much more "quiet" sine oscillator than any chip.

Like the rc phase shift oscillator using transistor.

 

That's the one;

 

That's the one;

Although I didn't use this oscilltor often, but I really had a little story about this oscilltor about 27 years ago.