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As part of a school project, I need to measure milliseconds from the start of a timer. I will need that value to later process it, subtracting and adding it later multiple times. At most the timer will last 5 seconds.

I have a clock signal with a frequency of 1kHz, what component can I use as a counter?

In school we've studied the theoretical components, but I need one(or more) actual IC that can count up to 5000 (probably 2^13). The only operations i need to do are add 1 and reset.

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    \$\begingroup\$ If your goal is something useful, with human readable display or transfer to a computer, etc, a cheap microcontroller will do a better job at this (relatively slow) counting rate. However, if you want to do it with digital logic, that's certainly valid as a learning project, even if it means the portion of the circuit you construct may be more complicated. Before the cheap-MCU-in-everything era there were also event/frequency counter chips which would directly drive 7-segment LED displays - ICM7216, etc. \$\endgroup\$ Commented Sep 26, 2016 at 13:10

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CD4040 (arguably the base product) & CD4020, CD4024, CD4060 are a counter/divider family that divide by 2^N. Some have all stages output but fewer stages. Some have more stages but not all outputs available. You can divide 1 kHz by 10 bits = 1024 divide = 1.024s/transition or you can use simple feedback to reset the counter at 1000 counts. You can use more or less stages as desired.

TI CD4040 famiy datasheet
Fairchild CD4040 family datasheet

The diagram below (from the Fairchild data sheet) shows the block diagram of the 4040 4020 and 4060 counter/dividers. It can be seen that the 4040 has all outputs accessible and tghe others do not, but they have more stages. These dividers can be "chained". By detecting the 1000 counts state a reset pulse can be generated turning eg a 4040 into a divide by 1000. A simple diode gate with diodes from outputs 10 9 8 7 6 4 to reset and a pullup resistor on the reset line will reset the counter at count 1111101000 = 1000 base 10 giving a 1 Hz output for 1 kHz in.

enter image description here

OR there are dedicated divide and display ICs that do this at a higher level.

OR Easiest fastest and possibly cheapest overall is to use a low cost microcontroller (Arduino clone or other). That would also be the most flexible solution.

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  • \$\begingroup\$ Arduino, I know... I already have built this project with it, now i have to do it with single ICs, a royal pain in the (‿ˠ‿). Any chance this component is in Multisim? \$\endgroup\$
    – sassoPera
    Commented Sep 26, 2016 at 13:46
  • \$\begingroup\$ @sassoPera Good! Pain in the (‿ˠ‿) usually mean you will learn something form it ;-) \$\endgroup\$
    – winny
    Commented Sep 26, 2016 at 13:48
  • \$\begingroup\$ HeHe, there is a reason I'm not waiting for the prof to explain how to do it right? :-) \$\endgroup\$
    – sassoPera
    Commented Sep 26, 2016 at 15:50
  • \$\begingroup\$ @sassoPera Do the ICs I suggested sound suitable? Are they in multisim? \$\endgroup\$
    – Russell McMahon
    Commented Sep 26, 2016 at 16:22
  • \$\begingroup\$ @RussellMcMahon Absolutely! They also are on Multisim, so I will surely mark yours as the right answer just as soon as I simulate the test circuit I'm making \$\endgroup\$
    – sassoPera
    Commented Sep 26, 2016 at 16:32

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