Hello I have a question for startup time for 32kHz of nRF51422. nRF51422_PS v3.1 indicates startup time for 32kHz typ 0.3sec.
What is this spec minimum value. I’d like to know approximately value of this spec.
Hello I have a question for startup time for 32kHz of nRF51422. nRF51422_PS v3.1 indicates startup time for 32kHz typ 0.3sec.
What is this spec minimum value. I’d like to know approximately value of this spec.
Hi Håkon
Thank you for your answer. If I use the crystal that startup time is 80msec, is that OK for nRF51422 ?
And would you tell me what "tstart,x32k" is meant. I think that it means if startup time of the crystal what I choose below the value, it works with no problem.
regards
Hi Håkon
Thank you for your answer. If I use the crystal that startup time is 80msec, is that OK for nRF51422 ?
And would you tell me what "tstart,x32k" is meant. I think that it means if startup time of the crystal what I choose below the value, it works with no problem.
regards
The parameter tstart,x32k is an example-startup time for a external 32k crystal. What is important when choosing an external 32k crystal is that you are within the maximum parameters specified in chapter 8.1.5. (CL,X32k / C0,X32k / RS,X32k)
I think that CPU normally waits for clock stabilization, it's not for 32kHz clock? It's for the only 32M/16M Hz?
It's not necessary to consider the stabilization time of 32 kHz?
You'll have to wait until the xosc32k is stable, which is the parameter tstart,x32k. This will be in the range of up to 1 second, depending on what type of extern 32k xtal you choose.
So, if I choose external 32k xtal that startup time is 80msec(measurement value), it's no problem ?
No problem, as long as your chosen xtal is within the max. parameters I mentioned earlier. it might vary from hundreds of milliseconds, up to a second. It all depends on the physical parameters of your chosen 32k xtal.