CC2642R-Q1: Crystal Start-up time

Hiroki Hatsuda

Part Number: CC2642R-Q1

Hi.

I would like to measure the startup time of 32kHz and 48MHz external crystal. Please tell me how to measure them.
Since I don't know the power supply timing of the oscillator circuit, is it impossible to measure them?

over 5 years ago

0 PM over 5 years ago

TI__Mastermind 27145 points

Hi,

We will look into it and get back to you ASAP. Please bear with us.

Thanks,

0 Hiroki Hatsuda over 5 years ago in reply to PM

Intellectual 430 points

Hi,

I would appreciate it if you could get back to me right away.

Hiroki

0 FI over 5 years ago in reply to Hiroki Hatsuda

TI__Mastermind 21290 points

Sorry for the delay here:

You can use this app note to calculate startup times:

http://www.ti.com/lit/an/swra495g/swra495g.pdf?&ts=1589235474817

Regards

0 Hiroki Hatsuda over 5 years ago in reply to FI

Intellectual 430 points

Hi,

Thank you for your information.

Is it possible to measure the startup time, not the calculation?

BR Hiroki

0 Hiroki Hatsuda over 5 years ago in reply to Hiroki Hatsuda

Intellectual 430 points

Hi,

Could you share measurement result of startup time(32k, 48M crystal) of launch pad.

We have measured.
The result was adout 303us at 48MHz and 216ms at 32kHz.

I would like to confirm if this measurement result is valid.

0 FI over 5 years ago in reply to Hiroki Hatsuda

TI__Mastermind 21290 points

Hi,

303usec for 48MHz seems right but 32kHz seems long. I will check 32kHz and get back.

Also, you can route the 32kHz clock on the GPIO and test it.

Is this how you are measuring the 32lHz startup time?

Thanks.

0 Hiroki Hatsuda over 5 years ago in reply to FI

Intellectual 430 points

Hi,

I measured by applying a probe to the X32k_Q1 terminal.

The firmware used was customized based on Project Zero in SDK3.4.

I am waiting for the confirmation result of 32k.

0 Hiroki Hatsuda over 5 years ago in reply to Hiroki Hatsuda

Intellectual 430 points

Hi,

What about the 32k startup time result?

I would appreciate it if you could get back to me right away.

0 Hiroki Hatsuda over 5 years ago in reply to Hiroki Hatsuda

Intellectual 430 points

Hi,

I would appreciate it if you could get back to me right away.

0 FI over 5 years ago in reply to Hiroki Hatsuda

TI__Mastermind 21290 points

Hi,

They typical startup time for 32khz crystal is 60-80msec.

Regards

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CC2642R-Q1: Crystal Start-up time