Context: This is a home brew project that incorporates NO microcontrollers as a learning exercise. I need to time something up to 20 seconds long, down to the nearest 100th of a second, and display the time interval measured. I'm using a 4 digit 7 segment common cathode led for the display.
I have a 100khz crystal and I want to display the tens, ones, tenths, and one hundredths of seconds (ie 23.36 seconds) on a 4 digit 7 segment led display. I thought I could use the 4026 chip, a decimal counter and led driver. However I have to chain 3 of them just to get to 100hz, then chain another 4 of them to get the 4 digits of display. 7 ICs (plus multiplexing logic because the display uses common abcdefg leads, plus resetting etc) seems like a LOT.
Am I missing a much simpler way to approach this? The 'rules' are: any ICs or other components but no software (no MCUs).
Keep it simple. You can find ICs that will divide the 100 kHz by 1000, like the 74HC4059 programmable divide-by-N counter, but most of these will cost you an arm and a leg, where a couple of cheap 74HC390 counters will do. The HC390 is a dual BCD counter, so for the second you only need half of the IC, but it's cheaper than a single BCD counter.