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25

You've changed the requirements by a lot! Measuring something in nanoseconds is hard. Measuring something with a +-100 ns accuracy really isn't. A 10 MHz counter works perfectly fine for that, do 20 MHz if you want to be sure. Any modern 32 bit microcontroller (read: 2€ investment...) has timer/capture units that can do that for you. You've went from a ...


13

Luxury option: Time to digital converter chip, available from several manufacturers. Accuracy: picoseconds. AS6500 TDC7200 Easy option: Microcontroller timer in capture mode to measure pulse width, or time between two pulses. Pretty much any microcontroller will do the job, but accuracy will be at best one clock cycle, so you must choose a microcontroller ...


9

Your cheapest solution is going to be determined by the cost of your time , components and circuit board with debug time. In this case your best solution is a used 100 MHz counter off EBAY for $150 https://www.ebay.ca/itm/AGILENT-HP-5316B-HIGH-PERFORMANCE-FREQUENCY-COUNTER-100-MHz-LOOK-REF-330G/193032320482?hash=item2cf19f75e2:g:O8UAAOSws3ldSDHf


8

(basically +/- 100ns). Well then, a cheap 8-bit microncontroller like ATTINY2313 can be clocked at 20Mhz, then you can just use its timers in input capture mode and that will get you +/- 25ns precision at each end of the pulse for over-all +/- 50ns precision (modulo clock jitter and innacuracy so use a good crystal for the clock) 75ns accuracy should be ...


7

I think the most realistic approach here is probably still a bit tricky: First of all, you'll have to realize that your signal has a pretty high bandwidth, assuming that the rise time of your pulses needs to be pretty steep to even get the required timing accuracy (e.g. if your rise time is 40 ns, then in 1 ns of an edge not that much voltage difference ...


4

Since you imply that 10 ns resolution is acceptable, a 50 OR 100 MHz timer can be built with either 10K or 100K ECL, or Schottky TTL (74Sxx or 74ASxx). You will need an accurate 50-100 MHz oscillator to clock the counters, and this is not a simple thing to design. Note that at your frequencies, the display will be updating far more rapidly that the eye can ...


4

Counting pulses with 1ns precision is a tall order. That rate rules out all the commonly used logic families like 74XX, CD4XXX, etc. Even the "high speed" varieties are nowhere near fast enough. That leaves you with ECL (Emitter Coupled Logic) as the next step up. These are fairly expensive and use a lot of power but when that's what you need, ...


4

Flip-flops (edge-triggered D type) serve several purposes in computer architectures: as sequential state registers (e.g., program counter) as cycle-delay elements (pipelines) that break up combinatorial paths as fast storage elements (registers) for holding data The cycle-delay use is important. It allows the clock speed to be increased because long ...


2

Can this be done without oscillators or pulse counting stuff? Yes, but it's going to be difficult to get the precision you want. A circuit using several 555 timer ICs will do the job but you'll have to spend time trimming all your resistor and capacitor values to get the timing as you want. But "yes", it could be done. If this were my problem, I'...


1

This very clearly calls for about any microcontroller: It's a discrete-input discrete-time (that's the definition of digital!) control problem. The power consumption of microcontrollers is negligible. Programming a microcontroller is way easier than implementing something analog that allows for such large time delays with a reasonable degree of ...


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