Hi
I need to build a simple frequency counter 3mhz max
and connect it to 7 segment or lcd display.
i need the most efficient way with minimum parts.
can someone help me.

__________________
Thank You
Ronnie

 

How many digit readout would you prefer? If you want to readout down to Hz you will probably need 7 digits.

__________________
The great thing about electronics is unlimited ways to do the job. The only limit is one\'s imagination. I generally think my way is best.
Show me a different way. I have an open mind.

 

I need at least 6 digits

__________________
Thank You
Ronnie

 

The circuit on this data sheet is one idea. In addition to the parts shown it with require an accurate time base and some control circuits. The timebase will need to be as low as 1Hz. The accuracy of the 1Hz will determine the accuracy of the counter.

http://www.jameco.com/cgibin/ncommer...search=13709CL

When you get to this page scroll down and click on the data sheet, it is about 13 pages in PDF format. The part is a CD4553N, it is a 3 digit counter in a 16pin dip.

__________________
The great thing about electronics is unlimited ways to do the job. The only limit is one\'s imagination. I generally think my way is best.
Show me a different way. I have an open mind.

 

thanks
I think the cd4026 decade counter is more simple,
less components,(good only for cc 7 segment),
the problem is i need 6 of them to have 6 digit.

__________________
Thank You
Ronnie

 

simplicity is importent,
don't care using lcd or pic like 16f84
i need minimum components. 8)

__________________
Thank You
Ronnie

 

Maxim makes a counter, part number ICM7217A, which drives 4 common cathode LED displays per chip. Use 2 of those (ignoring the extra digits you don't need) with a suitable timebase and you're there. Here's a link to the ICM7217A datasheet:
http://pdfserv.maxim-ic.com/en/ds/ICM7217.pdf

Hope this helps you. JB

 

This is common design nowdays but it requires PIC to be programmed

http://www.piclist.com/techref/piclist/weedfreq.htm
or
http://www.qsl.net/om3cph/counter/led/counter2.html
or
http://www.specs.de/users/danni/appl/soft/c51/frequenc/

If that's something you don't want to do, consider using few chips solutions like CD4026 or MC14553.

Probably the simplest way (very primitive but efficient) to reduce
components count is to not use decoding in hardware like using
multiple stage binary counter driving LEDs (two CD4020s would do).
You will need calculator to convert binary value to decimal.


Or just go and buy one:
http://www.aade.com/dfd.htm

 

Hi
i dont't know the ICM7217A component so i checked it and its good but expencive and i know other component better i think,its the max7219
with it you can drive 8 seven segment.
http://ee.cleversoul.com/max7219.html

the other links i allready know them,i need only measure up to 3mhz not more, like the 120mhz.
I think it can be done with 74hc4060 or 74hc4040 but i need a little help.

__________________
Thank You
Ronnie

 

Dear admin2far,

I hope to find the way to put this nicely and not sound rude.
If current replies are not helping enough, you might be better of
by simply buying the working unit or kit. They are not too expencive.
They are certainly much more affordable than waiting for someone
to roll out newer chip like 7226 or 7216. Those days are over.
The 7219 is only a driver chip, not counter. It simply turns on and off
LEDs based on command received serially. To turn it into frequency
counter you still need microcontroller to do the hard job of counting
and send the data in right format to 7219 chip.
If you have to go through hurdle of microcontroller than one chip
would do it all. If you don't like LCDs fine, you can have 6-7 digit
frequency counter with LED displays (Halicky) for either common anode
or common cathode. One thing is for sure, nobody will roll out
red carpet for customer willing to spen $20 if the equivalent product is
sold for $200 and more. That's one of the reason people are visiting
this forum and making things themself. The extra effort is a tradeoff
for cheaper product. We all have to live with it. (there is saying to
"put up or shut up"). I wish there was a one chip solution or better yet
an inexpencive integrated module that could be easily fitted into any of my projects.
PIC programmers are cheap to make and PIC chips are only few dollars.
Chips like PIC are what caused retirement of the ICL7216 nd ICL7226.
Maybe you can find someone close by who can program one for you
(or send it to you). You don't have to learn how to write programs.
They are posted on the links above. Just build small programmer on
protoboard, get PIC and crystal. Dump provided code into chip and
you can use it. This is pretty much the "least number of component"
solution of today.

 

Hi
thank you for your answer,i didn't ment to upset you,
i saw a circuit- prescaler divide by 1000, 3ghz divide by 1000 gives 3mhz,
and i wanted to display these frequencies.
i am creating a new web site with kits,so i am looking for interesting projects to sale.
again sorry for any inconvenience. :cry:

__________________
Thank You
Ronnie

 

Gee Ronnie,

I tought this might not go well and now I feel bad so please forgive me.
I understand the enthusiasm of making device like this because
I was making them myself too.
I wasn't upset, just tried to make a point that "dirt cheap, simple
and few components" doesn't mix well with project like this as
was pointed in few replies.
BTW, if you are into making kits etc. you probably should
be considering microcontrollers. They run the world (literally)
and are a lot of fun (with mybe some frustration on occasion...).

panic mode (diplomat in making)

 

Hi
I have a frequency counter from maplin.co.uk, it cost me 60-70 pounds,
I wanted to sale in my site much cheeper versions of this counter,cheeper and good sometimes they meet:-)
I am working on a pic version and i wanted to build a without pic version and compare them.
the cost of the pic version is no more then 20 dollars!!!
so why should customers pay a lot of money for an item
if they have cheeper options?!
I am trying to give them more options.
I like very much the "maplin" web site and buy there quite offten.
frequency counter price in other sites is 80-100 dollars,
I allways check before i buy something.
Some times i ask too much questions,i know and i am sorry.
This site is one of my favorites.
bye

__________________
Thank You
Ronnie

 

Have you looked at CPLDs (A programable logice device)? You can get a decent one from xilinx for less than $5. All you need to do is program in a counter, a timer and a couple 7 segment decoders. The Coolrunner 2 claims speeds up to 200MHz so 3 MHz should be easy. Xilinx has free software for all their CPLDs. You should be able to do it with 3 ICs - CPLD, Clock driver and a regulator.

 

Thanks
I will check it.

__________________
Thank You
Ronnie