What no more 7494?

[muso52]

Hi Guys,

Have just looked for a 7494 asyn ripple through counter and apparently its now obsolete (me aswell)
Is there an off the shelf chip that will do the following?

Async divide/counter, serial in par out, TTL .
I am cheating I know but If anyone has any ideas then I'd appreciate it.

Willy

 

[MrAl]

Hi,

Did you look for the LS version, 74LS94 ?

 

[muso52]

Hi,

Did you look for the LS version, 74LS94 ?

Yep no luck, surprised that I cant find anything suitable, 4 flip flops is a bit of a pain.
Willy

 

[tunedwolf]

I think Nikko Electronics still carry the 74LS94

 

[muso52]

Hi tw,
many thanks for the heads up. Also for bringing Nikko to my attention'
Willy

 

[muso52]

tw,

74LS94 is par in serial out.
any other ideas?
willy

 

[ericgibbs]

hi 52,
The original 7494 is a parallel to serial S/R.

 

[tunedwolf]

As Eric pointed out, the 7494 is a parallel to serial device containing 4 R-S flip flops. Although I mentioned the 74LSxx version from Nikko, I have no idea on the quantity that you need. If it's only a couple for a one off repair or proof of concept etc, then you can find them on the 'bay in small quantities: https://www.ebay.co.uk/itm/Texas-In...al_Components_Supplies_ET&hash=item3a7700b960

 

[Ian Rogers]

Does it have to Asyncronous reset? the 74ls90 is syncronous ripple counter!!

 

[Mike odom]

Did you look at the 74AHC594?

 

[muso52]

Hi Gents,

Many thanks for your time and info. I feel it only right to admit to a little confusuion now in that what I was looking for in the O/P was maybe wrong. Perhaps if I tell you what I am trying to achieve would be more sensible. I am looking to divide a clock pulse by 4 out-putting on 4 individual outputs from a serial clock input. This clock input is derived from a 4017 decade counter (for a divide 10 function) which is fed from a V to F convertor a TC9400. Now I thought that I could use this latter device to divide by 4 utilising the MR but no go. As the reset does so on the trailing edge it efectively places a 'hic-up' in the chain by missing an incoming clock pulse. So by divide by 4 is a 4 beats followed by one of silence so to speak.
Basically what I am after is a sequencer or chacer circuit I would imagine akin to a four channel disco light sequencer.
The speed of the 'chase' being dependant on the clock pulse rate from the TC9400. Any ideas would be most welcome.

Willy

 

[ericgibbs]

hi,
It should be possible to divide by 4 using the correct sense for the 4017's input clock, and to Reset the 4017 back to pin3 '0' on Q4 pin10.
E
Do you have a circuit diagram of your version to post.?

 

[ericgibbs]

hi 52,
This is a divide by 4 chaser.

 

[muso52]

Hi Eric,


Yep you correct. Working fine now. Thanks go to you and also the others for there interest and comments.
Regards,
A still learning
Willy