RTC clock issue

Autonomous Machines Jetson & Embedded Systems Jetson TX2
1

Hi ALL
i have a RTC issue. but i don’t know the reason.

this is my test step

  1. device have rtc battery and disconnect ethernet.
  2. Boot up the system
  3. Use manual mode to modify the date
  4. Power off the device
  5. unplug the AC adopter.
  6. After 24 hours, Connect AC adopter and Power on
  7. Clock is 2 t or 3 second fast (or slow )

how to trace this issue?

2

Onboard crystal oscillators typically drift, and so I would think 2 or 3 seconds is normal and expected. More accurate crystals can be used, but often they include a temperature control by means of a heating resistor (they use more power). Even this isn’t particularly accurate. I wouldn’t know what the best means is to provide an external clock source, but for precision you will need one of network source, GPS radio sources (which is basically the same as a network time setting, but over radio), or an external precision clock. What are your accuracy requirements?

3

Hi, Can you provide current RTC actual accuracy specifications of TX2?
This information is very helpful for us.

4

Someone else may have the RTC drift specs, but I do not have that information.

5

The XTAL tolerance is +/-20 ppm @25C and max -0.04ppm/C2 of frequency-temperature coefficient.