I am doing some research for a quick microcontroller to measure some pretty sort time differences and was wondering if you guys know what microcontroller has the fastest timer. The MSP340 from TI has a 5ps resolution but its development board is really expensive and I am not familiar with TI's microcontrollers. The next fastest I found is the STM32F334 with 217ps resolution and the KV5x (NXP) with 260ps resolution. Are there any other offers that I missed?
thanks

 

Timers generally derive their clocks from the core MCU clock. Hence you cannot generalize on the speed of any family without looking at the specs of specific components.

Take a look at the STM32H743 that can be clocked at 400MHz (2.5ns resolution).

Edit: I see that STM32F334 has a high-resolution timer that is clocked at 144 x 32MHz to give 217ps resolution.

I have not been able to read read how the MSP430FR6047 can achieved <5ps. I believe this is embedded in the ToF measurement in the USS software.

 

Upon further investigation, the STM32F334 seems to have a resolution of 217ps only for output and not for capture mode... Is that correct? I can't measure time between two events with this resolution?


So the only solution is a TI chip???

thanks

 

I'm on the trail. When I get back to base camp I have to look into how the MSP430FR6047 can achieve <5ps. That is incredible!

 

I would also like to know how a TI MSP430 has a timer at <5ps and, frankly, I am skeptical. I was looking at this a bit this morning and the D timer on the TIs that you seem to be referring to run at 256 MHz and that is a period of just shy of 4 ns and the CPU is at, what, 25MHz.

So, yes, I would like to know how that is possible and what I am missing.

Here are two interesting threads that might interest you:

https://electronics.stackexchange.com/questions/59216/very-accurate-time-measurement

(note the reference to a 1GHz overclocked RPi?!!)

https://www.researchgate.net/post/is_there_a_processor_which_provides_Nano_second_timer

(discussing the use of counters outside of the microcomputer)

 

On further research, the TI MSP430FR6047 does NOT have <5ps timer resolution.
That capability quoted by TI is the ToF (time-of-flight) resolution of the USS (ultra-sonic sensing) technique for measuring ultra-low flow rate for metering applications.

http://www.ti.com/lit/ml/swmp003/swmp003.pdf

http://www.ti.com/lit/wp/sway007/sway007.pdf

The ADC samples the data at 3.6Msps. The data is processed to extract the differential ToF (forward and reverse ToF between two sensors). The <5ps quotation is the resolution after processing.

 

Nice catch. I don't know if i'll go that route then unless i find some examples (i'll have to look into that). Another option is combining any microcontroller with the TDC7200 (time-to-digital converter) chip which has a 55ps resolution and is accessible via SPI. So the fastest timer is on the new stm32h743 with a 2.5ns with 4.5MSPS. The TI MSP430FR6047 has 8MSPS. Also, for the KV5x from NXP, the 260ps resolution is also for PWM.
thanks guys