How to measurement 32k start-up time?

[vicchengc]

Dear teams,

 I use the passive probe to measurement 32k start-up time ,but my boss tell me is wrong .The passive probe has the about load effect. Can you tell me how to correct measurement 

Thanks

[igorpadykov]

Hi Vic

it is necessary to use high impedance probe, also may be useful to look at

AN2907 32 kHz Oscillator Start-up Time and POR Pulse Width Considerations

https://www.nxp.com/docs/en/application-note/AN2907.pdf 

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[vicchengc]

Hi igorpadykov,

Thanks for the useful reply.

I use one  probe not only has high impedance but also has high load capacitance.

According to the application note : Adding capacitance  will affect oscillator performance. It let me confuse

Thanks