# simple clock divider by 10

Discussion in 'General Electronics Discussion' started by aletropot, Feb 24, 2016.

1. ### aletropot

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May 12, 2013
hi all,
what would be a simplest schematic (or single chip) for a clock divider by 10?
thnks

1,096
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Oct 26, 2011

3. ### AnalogKid

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Jun 10, 2015
Or, a 74HC90 (or any other 7490 variation) can divide the input frequency by 10 and produce a symmetrical output.

ak

davenn likes this.
4. ### signalman72

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Jan 26, 2014
I built a nixie clock that uses 4017 decade counters. It uses a flip flop to turn incoming line frequency (USA, 60 hz) into a square wave pulse train. Then one 4017 divides it by ten producing a 6 hz output. The next 4017 divides it by 6 producing a 1 hz frequency for a clock pulse.

5. ### aletropot

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May 12, 2013
I mean, not using a decade counter...
In my case, space is a problem and bacause i dont need to go smd, if there is a simple schematic that do the work without being a decade counter/clock divider, etc

6. ### cjdelphi

1,096
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Oct 26, 2011
An attiny85 if you wish....

7. ### Harald KappModeratorModerator

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Nov 17, 2011
Divide a clock by 10 without using a clock divider.... what an idea.

Suitable as long as the clock frequency is not too high for the µC to handle. And very small.

8. ### AnalogKid

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Jun 10, 2015
Space is a problem, but you don't need to go with surface mount parts?
You want to divide a digital clock signal frequency by ten, but without dividing it by 10?

ak

9. ### Harald KappModeratorModerator

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Nov 17, 2011
Thinking a bot about this matter, yes, it can be done, albeit only within a very limited range of input signals. I made an analog circuit that needs to be fine-tuned to the input signal. Neither elegant (compared to a digital divider) nor space saving, but an out-of-the-box solution:

red = input clock
blue = output pulse train at 1/10 input rate.

10. ### AnalogKid

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Jun 10, 2015
Yeah, I remember an old UJT frequency divider circuit that is basically the same thing. If the frequency were low enough you could use an LM393. Not the traditional choice for frequency division...

Somewhere on the innergoogle is an analog clock based on this - a digital display clock with 100% of the timing circuits done by integrators and comparators.

ak

11. ### cjdelphi

1,096
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Oct 26, 2011
I guess the question begs, what's the frequency?

12. ### Harald KappModeratorModerator

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Nov 17, 2011
True for the digital or analog circuit.
The analog circuit can be made more robust to frequency variations (within limits) by adding a pulse shaper on the front end: A differentiator plus a monostable mzltivibrator to ensure constant input pulse length regardless of frequency (at least up to an upper limit where 1/f=pulse length). At low frequencies the losses of the circuit which discharge C1 limit the operation.

13. ### aletropot

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May 12, 2013
attiny85 has to be programmed but sounds good.
I was looking for analog circuitry, if theres any schematic that can be made to divide a clock signal by ten.
If theres not I'm ok with a no.

thanks Harald Kapp. that seems what im talking.

Last edited: Feb 25, 2016
14. ### Gryd3

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Jun 25, 2014
I'm enjoying the need to be space concious, but also requiring the use of multiple components instead of a decade counter that measures at most 27mm x 8mm for the largest 20 pin package xD

Aletropot. What is your size limit, and why do you require a solution that is not a decade counter?
I don't understand this design limitation... what is the source you are using for the clock you wish to divide by 10?

15. ### aletropot

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May 12, 2013
I did a pcb with test grid 6x6. 4017 dont fit on it.
its just to avoid to make a small pcb for this extra chip. but the counter must be the easier solution

16. ### AnalogKid

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Jun 10, 2015
I'm still confused. First, why do you want to divide the frequency with an analog circuit? There are many ways to do this, but rambling through all of them with no direction just seems like a waste of time. Second, if this is your first choice, how is a microcontroller that needs to have firmware developed and programmed an acceptable alternative, yet a simple divide-by-10 chip (50 cents, no programming) is not?

ak

17. ### Gryd3

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Jun 25, 2014
6x6 what? mm or cm?
You can always do deadbug style considering most pins won't be connected to anything useful.
There are SMD versions much much smaller.
A microcontroller will be close to the same size of a 4017, and the analogue approach will require so much more messing around to fit the components that it may not be worth it... look at the size of an OpAmp IC...

18. ### aletropot

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May 12, 2013
6x6 holes.
haha.. deadbug style. i'll cut an extra small veroboard and make a kind of platform for the 4017. easier and not lose
was just trying to use what i have here.

19. ### Harald KappModeratorModerator

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Nov 17, 2011
Using analog electronics to divide a clock signal is most unusual. My little circuit was meant more as an exercise. You'll find that in a real environment it will show issues with stability and accuracy.

20. ### AnalogKid

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Jun 10, 2015
If the input signal is a fixed frequency, this can be done with a 7414, 4093, 393, or, of course, an LM358.

ak