Electronics > Projects, Designs, and Technical Stuff
20 bit up/down counter, anything more elegant than a bunch of cascaded 4516's?
(1/4) > >>
Jester:
I need to build a 20 bit, binary up/down counter.

I don't need preload, but I do need all the bits, so 4040 etc. won't work.

I suppose I can cascade a bunch of 4516's, just messy with only 4 bits per chip. The 74...869 is 8 bit, but they are really expensive. There must be a better solution other than programming a small uC?

I feel like I'm missing something even after searching up/down counters with google.

Kleinstein:
I don't know common up/down counters with more than 4 bits. There are difference version how up/down are combined.
The 4040 has all the outputs for 12 bits - however it is just a simple counter, no up/down.

As an alternative to a µC, there are also CPLDs, programmable logic chip that should be capable to do up/down counting for quite some bits.
Benta:
I agree, the 4516 (or 74HC types) are probably the solution if you want to avoid CPLDs. At least they're cheap :)
scuzzyTerminator:
A parametric search at digikey found these 8-bit devices pretty quick. Is TTL OK?

SN74AS867, SN74AS869: http://www.ti.com/lit/ds/symlink/sn74as867.pdf

Benta:

--- Quote from: scuzzyTerminator on December 30, 2018, 11:09:12 pm ---A parametric search at digikey found these 8-bit devices pretty quick. Is TTL OK?

SN74AS867, SN74AS869: http://www.ti.com/lit/ds/symlink/sn74as867.pdf

--- End quote ---

Read the OP. He already found those...
Navigation
Message Index
Next page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod