LM566 alternative.

[Kevin Glover]

I have benn trying to find a decent alternative to the LM566 VCO. It
does not seem to be sold anymore at reputable sellers and the ones on
EBay (from China) I don't trust to be authentic or unrecycled. Does
anyone know of a 8 to 16 pin alternative (just square and triangle
out) that won't break the bank.
Thanks
-Slackmeister

[Jim Thompson]

What is your frequency range?

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I'm looking for work... see my website.

[Kevin Glover]

On Thu, 18 Aug 2016 20:15:26 -0700, Jim Thompson
<To-Email-Use-Th...@On-My-Web-Site.com> wrote:

>On Thu, 18 Aug 2016 19:38:30 -0700, Kevin Glover
><kevinf...@yahoo.com> wrote:
>
>>I have benn trying to find a decent alternative to the LM566 VCO. It
>>does not seem to be sold anymore at reputable sellers and the ones on
>>EBay (from China) I don't trust to be authentic or unrecycled. Does
>>anyone know of a 8 to 16 pin alternative (just square and triangle
>>out) that won't break the bank.
>>Thanks
>>-Slackmeister
>
>What is your frequency range?
>
> ...Jim Thompson

Purely audio band. For audio synth modules.

[Jim Thompson]

On Thu, 18 Aug 2016 19:38:30 -0700, Kevin Glover
<kevinf...@yahoo.com> wrote:

Looks like the EXAR XR2206 is still available (at Jameco)...

<http://tinyurl.com/5l2k3j>

Of course you can make a quite respectable VCO with a 555 Timer and
some transistors.

This book...

<http://makezine.com/2008/08/06/review-the-vco-chip-cookb/>

might be helpful to you.

[George Herold]

If you are in the US/Canada and only need a few (10-100) I've got a few tubes
of ICL8038's.
Which I think is the same as the Exar part JT linked to.

George H.

[Kevin Glover]

I'm experimenting with a VCO cluster(aka Cloud) and need a number of
basic VCOs. If you're willing to part with a few, I'm interested.
I found some on Amazon but many are from China and one doesn't know if
they are new or reclaimed. If yours are new in the tube then I'd be
interested.
I'm in California. E-Mail me if you wouldn't mind selling a few.
Thanks
-Kevin

[upsid...@downunder.com]

On Thu, 18 Aug 2016 19:38:30 -0700, Kevin Glover
<kevinf...@yahoo.com> wrote:

Have you searched for PLLs and only use the VCO part of it ?
Unfortunately, the low pin count devices usually have internal
connection between the phase detector and VCO, but try to find one
without such internal connection.

[Phil Hobbs]

>Have you searched for PLLs and only use the VCO part of it ?
>Unfortunately, the low pin count devices usually have internal
>connection between the phase detector and VCO, but try to find one
>without such internal connection.

+1

The VCO of the CD4046 might be a good candidate. It's reasonably linear, though its output is a square wave whose duty cycle isn't that we'll controlled.

cheers

Phil Hobbs

[upsid...@downunder.com]

According to the old (1974) Signetics application note, the NE566 VCO
is NE565 PLL with th phase detector disabled. The application note
also shows how to control the NE565 VCO by injecting the control
_current_ into pin 8, effectively bypassing the PD.

[George Herold]

Yeah and the 74HC4046 is less good.

George H.

[Clifford Heath]

For values of "less good" that are roughly speaking, awful.
Very hard to get better than 10:1 ratios, vs 1000:1 with HC4046.

[Spehro Pefhany]

I like the roll-your-own one with a single BJT or MOSFET and 1/2 an
LM324. Triangle out from the integrator and square wave output from
the comparator. You can shape the triangle wave into a facsimile of a
sine wave but that gets more complex or requires trimming.

---sp


--
Best regards,
Spehro Pefhany
Amazon link for AoE 3rd Edition: http://tinyurl.com/ntrpwu8

[Mike Perkins]

I have some experience of the 74HC4046 and it's one device where there
is an enormous spread in VCO characteristics amongst manufacturers. In
the end I tested a few and settled on what is now NXP.

YMMV

--
Mike Perkins
Video Solutions Ltd
www.videosolutions.ltd.uk

[Tilmann Reh]

Kevin Glover schrieb:

You might have a look at the LM331 also.

Tilmann

[P E Schoen]

"Kevin Glover" wrote in message
news:h1scrbh3b2khj2hpf...@4ax.com...

I think I have one or two tubes of Teledyne 9400CJ which are probably
equivalent to the Microchip part TC9400. It is a 14 pin IC and good from DC
to 100 kHz.

I found this datasheet for the LM566 as parts inventory at msu.edu:
https://www.egr.msu.edu/eceshop/Parts_Inventory/datasheets/lm566.pdf

The TC9400:
http://ww1.microchip.com/downloads/en/DeviceDoc/21483d.pdf

It's available from Mouser for about $9:
http://www.mouser.com/ProductDetail/Microchip-Technology/TC9400CPD/?qs=sGAEpiMZZMuYYilu8wI%252bZ8hERa3rWPKvbXhFsjlaxFE%3d

I also might have some Analog Devices AD537, also from Mouser for $67 each
(gold plated)!
http://www.mouser.com/ProductDetail/Analog-Devices/AD537JD/?qs=sGAEpiMZZMv9Q1JI0Mo%2ftXXGwciEHipU
http://www.mouser.com/ds/2/609/AD537-877110.pdf

You might also look at LM331:
http://www.ti.com/lit/ds/symlink/lm331.pdf

and KA331 (Only about $0.50 at Mouser)
http://www.mouser.com/ds/2/149/KA331-58235.pdf

email: paul at pstech-inc dot com

Paul

[Jim Thompson]

On Fri, 19 Aug 2016 23:25:23 -0400, Spehro Pefhany
<spef...@interlogDOTyou.knowwhat> wrote:

>On Thu, 18 Aug 2016 19:38:30 -0700, the renowned Kevin Glover
><kevinf...@yahoo.com> wrote:
>
>>I have benn trying to find a decent alternative to the LM566 VCO. It
>>does not seem to be sold anymore at reputable sellers and the ones on
>>EBay (from China) I don't trust to be authentic or unrecycled. Does
>>anyone know of a 8 to 16 pin alternative (just square and triangle
>>out) that won't break the bank.
>>Thanks
>>-Slackmeister
>
>I like the roll-your-own one with a single BJT or MOSFET and 1/2 an
>LM324. Triangle out from the integrator and square wave output from
>the comparator. You can shape the triangle wave into a facsimile of a
>sine wave but that gets more complex or requires trimming.
>
>---sp

That's sort of the way I'd do it... except I'd use a package of
LM339's and make good triangles, and linear frequency versus voltage,
with current mirror control.

You can simply add current mirrors to a 555 and attain the same thing
more simply... but it's forbidden to even mention a 555 Timer on this
newsgroup >:-}

[JW]

On Sat, 20 Aug 2016 06:34:03 -0700 Jim Thompson
<To-Email-Use-Th...@On-My-Web-Site.com> wrote in Message id:
<3tmgrb1bhivi4ck73...@4ax.com>:

>On Fri, 19 Aug 2016 23:25:23 -0400, Spehro Pefhany
><spef...@interlogDOTyou.knowwhat> wrote:
>
>>On Thu, 18 Aug 2016 19:38:30 -0700, the renowned Kevin Glover
>><kevinf...@yahoo.com> wrote:
>>
>>>I have benn trying to find a decent alternative to the LM566 VCO. It
>>>does not seem to be sold anymore at reputable sellers and the ones on
>>>EBay (from China) I don't trust to be authentic or unrecycled. Does
>>>anyone know of a 8 to 16 pin alternative (just square and triangle
>>>out) that won't break the bank.
>>>Thanks
>>>-Slackmeister
>>
>>I like the roll-your-own one with a single BJT or MOSFET and 1/2 an
>>LM324. Triangle out from the integrator and square wave output from
>>the comparator. You can shape the triangle wave into a facsimile of a
>>sine wave but that gets more complex or requires trimming.
>>
>>---sp
>
>That's sort of the way I'd do it... except I'd use a package of
>LM339's and make good triangles, and linear frequency versus voltage,
>with current mirror control.
>
>You can simply add current mirrors to a 555 and attain the same thing
>more simply... but it's forbidden to even mention a 555 Timer on this
>newsgroup >:-}

That's complete BS. ;)

[Paul Badenhorst]

I have just seen your message. just thinking. Would it not be possible to use a LM565 's VCO. Would have to design a small board to fit the LM566 socket. If you could find them? also discontinued.

[Paul Badenhorst]

On Friday, 19 August 2016 at 04:38:37 UTC+2, Kevin Glover wrote:

I see i have two unused NE566E's.

[legg]

Now all you need is a time machine to transport them back
to 2016.

RL

[Phil Hobbs]

Re: Google Groups

Welcome to Usenet (not Google Groups). This group is
sci.electronics.design, which is actually older than Google.

It's entirely unmoderated and unrestricted, except for the generally
accepted informal rules, known as *netiquette*.

Don't let Rob discourage you--c'mon and join the fun.

Re: NE566

The 566 is a really crappy oscillator. It's perfectly okay for a
junkbox project, of course--I've done lots worse things myself--but for
a real design there are many, much better choices nowadays.

On the simple end, the oscillator of a CD4046 will work as a very
wide-range VCO with a pretty linear tuning characteristic over about
100:1 in frequency, though the center frequency isn't that accurately
controlled by the RC time constant.

The 4046 has only a square-wave output, so if that's a worry one could
use one of many dual op amps. One section would be a Howland current
source driving an integration capacitor with its other end grounded, and
the other would be a Schmitt trigger controlling the polarity of the
Howland. That will be better than the 556, but of course needs a lot of
extra resistors. (On a PC board, one could make both the Howland and
the Schmitt using one 8x resistor array, so it wouldn't be that many
parts in real life.)

Cheers

Phil Hobbs



--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

[Don Y]

No, they're likely already there! The issue is getting the INFORMATION
regarding their availability to the OP!

[Anthony William Sloman]

On Friday, July 29, 2022 at 12:43:13 AM UTC+10, Phil Hobbs wrote:
> Paul Badenhorst wrote:
> > On Friday, 19 August 2016 at 04:38:37 UTC+2, Kevin Glover wrote:

> Re: NE566
>
> The 566 is a really crappy oscillator. It's perfectly okay for a
> junkbox project, of course--I've done lots worse things myself--but for
> a real design there are many, much better choices nowadays.
>
> On the simple end, the oscillator of a CD4046 will work as a very
> wide-range VCO with a pretty linear tuning characteristic over about
> 100:1 in frequency, though the center frequency isn't that accurately
> controlled by the RC time constant.
>
> The 4046 has only a square-wave output, so if that's a worry one could
> use one of many dual op amps. One section would be a Howland current
> source driving an integration capacitor with its other end grounded, and
> the other would be a Schmitt trigger controlling the polarity of the
> Howland. That will be better than the 556, but of course needs a lot of
> extra resistors. (On a PC board, one could make both the Howland and
> the Schmitt using one 8x resistor array, so it wouldn't be that many
> parts in real life.)

Another option is to run the 4046 eight or 16 times faster than the sine wave frequency you need, divided it down by eight or sixteen, to get a square wave of the desired frequency, and clock the slower square wave through an eight or sixteen stage shift register at the faster clock rate.

By tacking the right resistor values onto the taps on the shift register , and running all the resistors into a summing junction you can make finite impulse response low pass filter and get a pretty clean sine wave over quite a wide range of frequencies, You use up a lot of E96 value O.1% resistors, and you have to worry about putting a Hamming window on your sinc function resistor vales to suppress Gibbs oscillations, but it can make a nice sine wave over a wide range of frequencies.

--
Bill Sloman, Sydney