1kHz oscillator

[Frank Birbacher]

Hi!

What is a cheap way to build an oscillator with a frequency of
about 10-30kHz which shall drive a logic, 8-bit up counter (e.g.
chip 74393)? The exact frequency is not important.

Frank

 

[Andrew Holme]

Frank Birbacher wrote:

Hi!

What is a cheap way to build an oscillator with a frequency of
about 10-30kHz which shall drive a logic, 8-bit up counter (e.g.
chip 74393)? The exact frequency is not important.

Frank

http://www.fairchildsemi.com/an/AN/AN-118.pdf

See FIGURE 6. Schmitt Trigger Oscillator

 

[Jim Thompson]

On Sat, 6 Nov 2004 17:02:45 -0000, "Andrew Holme" <andrew@nospam.com>
wrote:

Frank Birbacher wrote:
Hi!

What is a cheap way to build an oscillator with a frequency of
about 10-30kHz which shall drive a logic, 8-bit up counter (e.g.
chip 74393)? The exact frequency is not important.

Frank

http://www.fairchildsemi.com/an/AN/AN-118.pdf

See FIGURE 6. Schmitt Trigger Oscillator

See "CMOS-Osc-NoClip.pdf" on the SED/Schematics page of my website for
the proper way to make a stable oscillator.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Ken Smith]

In article <2v4cp6F102bh2U1@uni-berlin.de>,
Frank Birbacher <bloodymir.crap@gmx.net> wrote:

Hi!

What is a cheap way to build an oscillator with a frequency of
about 10-30kHz which shall drive a logic, 8-bit up counter (e.g.
chip 74393)? The exact frequency is not important.

I think you can use one of the resistor programmed oscillator chips such
as the ones from Linear.

A lot depends on what else in the circuit. Do you have a left over
comparitor or logic gate or transistor or any thing? Using up the left
over parts can really lower the cost.

--
--
kensmith@rahul.net forging knowledge

 

[Frank Birbacher]

Hi!

Ken Smith wrote:

I think you can use one of the resistor programmed oscillator chips such
as the ones from Linear.

*looking it up* Well, looks good. I can even order it. Wow, its 6
bucks each. Maybe I resort to this, if I don't find any other
reasonable solution.

A lot depends on what else in the circuit. Do you have a left over
comparitor or logic gate or transistor or any thing? Using up the left
over parts can really lower the cost.

No, nothing left. And don't try too hard. I don't want to save
every cent. Just every Euro

Frank

 

[Rich The Philosophizer]

On Sat, 06 Nov 2004 17:36:05 +0100, Frank Birbacher wrote:

Hi!

What is a cheap way to build an oscillator with a frequency of
about 10-30kHz which shall drive a logic, 8-bit up counter (e.g.
chip 74393)? The exact frequency is not important.

CD4060 - oscillator and counter in one chip.

Have Fun!
Rich

 

[Max Hauser]

"Frank Birbacher"in news:2v65j2F2gnau9U1@uni-berlin.de...

Ken Smith wrote:
I think you can use one of the resistor programmed
oscillator chips such as the ones from Linear.

*looking it up* Well, looks good. I can even order it.
Wow, its 6 bucks each.

Too much! It's $2.55 in small quantities at Linear's Web site ("buy now"
button) for the prototype of that family, the LTC1799 (1 kHz - 30 MHz). As
I remember, this product is also much cheaper in quantity (which would not
necessarily be ordered off the Web site with a credit card but from a
distributor or the firm directly).

 

[Frank Birbacher]

Hi!

Max Hauser wrote:

Too much! It's $2.55 in small quantities at Linear's Web site ("buy now"
button) for the prototype of that family, the LTC1799 (1 kHz - 30 MHz). As
I remember, this product is also much cheaper in quantity (which would not
necessarily be ordered off the Web site with a credit card but from a
distributor or the firm directly).

I only need one. But I have to order at least two. 2 times $2.55
= $5.10 . And how about shipping?

I will call a nearby German distributor tomorrow. I don't want to
pay by credit card neither, because I don't have one.

Frank

 

[Joerg]

Hi Frank,

I only need one. But I have to order at least two. 2 times $2.55 =
$5.10 . And how about shipping?

I will call a nearby German distributor tomorrow. I don't want to pay
by credit card neither, because I don't have one.

Why not just take a Schmitt trigger such as the 74HC14 and make a simple
oscillator, as the others have suggested? These parts should be
available in your cabinets or can be bought at the next electronics
store. For less than one Euro ;-)

Regards, Joerg

http://www.analogconsultants.com

 

[Frank Birbacher]

Hi!

Rich The Philosophizer wrote:

CD4060 - oscillator and counter in one chip.

I just looked at the datasheet. But that didn't convince me right
away. There are notes on the sheet which say don't supply less
than 7V when doing so and so. Minimum frequency 690kHz. Ok I can
discard the lower n output bits yielding 690kHz / 2^n.

Well, how do I figure out, which RC combination make the chip
oscillate at a low frequency? I'm totally confused with all the
things on the sheet.

http://www.ee.washington.edu/stores/DataSheets/cd4000/cd4060.pdf

Frank

 

[Frank Birbacher]

Hi!

Rich Grise wrote:

Like, do you already have the counter?

No, I don't. But I haven't thought of a counter and oscillator
combined in one chip.

The simplest way to do this is with a
schmitt trigger inverter, a resistor, and a capacitor. This is not
very stable or reliable, but it will meet your needs as you've said.

Ok. But how do I determine the frequency?

This has been suggested by about a dozen people. I can't understand
why you seem to be ignoring them, or is your server dropping posts?

I only see three responses to my original message. These are from
Andrew Holme (suggesting Schmitt Trigger), Ken Smith (Linear
chip) and you (CD4060). I don't see dozens of messages. My server
is News.Individual.DE.

Frank

 

[john jardine]

"Joerg" <notthisjoergsch@removethispacbell.net> wrote in message
newsrPkd.7729$zx1.6870@newssvr13.news.prodigy.com...

Hi Frank,

Ok. But how do I determine the frequency?

Well, if for example you'd like to use the 4060 just look at the data
sheet. It says right in there how to do the circuit and how to calculate
the frequency. Schematic, formula, graphs and all. It's just the usual
RC oscillator. Same if you'd want to use another chips like the 40106
Schmitt trigger and use that as an oscillator. With that one you could
actually make six oscillators.

Servus (assuming you are in Bavaria), Joerg

http://www.analogconsultants.com

I once tried to make a full 6 oscillators (over 5:1 frequency range) but
found gate to gate isolation not brilliant. The switching edges of each
section triggered chaotic operation of the others. They all then fed back
into each other. One day I'll try it again but only to check out the quality
of the resulting noise spectrum.
Best I've been able to use, is 2.
regards
john

 

[Joerg]

Hi John,

I once tried to make a full 6 oscillators (over 5:1 frequency range) but
found gate to gate isolation not brilliant. The switching edges of each
section triggered chaotic operation of the others. They all then fed back
into each other. One day I'll try it again but only to check out the quality
of the resulting noise spectrum.
Best I've been able to use, is 2.

That surprises me. Was that with good VCC bypassing? I can only talk
about SMT but there I never had any crosstalk or erratic behavior.
Usually I really squished out every ounce of use per chip, meaning all
six portions were running as one-shots, oscillators, pulsers and so on.
No issues there. Even when used as a controllable PWM oscillator where
any noise from the other five portions would have been a pain there was
no trace of crosstalk.

Regards, Joerg

http://www.analogconsultants.com