Clocking of CSI-2 video decoders

Good day!

We are developing a custom carrier for Jetson TX2. It should take 6 analog video streams and decode them to 6 parallel CSI-2 channels for Jetson to process.

We have chosen Analog Devices AD7282A-M ICs for the purpose.

By the documentation, the ICs should be clocked by the crystal oscillator OR by external clock generator of 28.63636 MHz.

The question is, should we fanout Jetson’s CAMx_MCLK to the ICs for synchronisation, or can we just clock them with quartz crystalls, as their documentation suggests?


hello lipado,

you may implement AD7282A-M as camera sensor driver,
please use an external clock source since the maximum frequency for extperiph1 is 24 MHz.
please also refer to documentation, Sensor Software Driver Programming Guide.
you may also access Tutorials page, expand [Developer Tools] session and check the [V4L2 Sensor Driver Development Tutorial].


I could not find the 24MHz limit for extperiph1 in the TRM and I could set it up to ~37MHz. How is the limit calculated and what happens if I exceed 24 MHz?

hello arne.caspari,

please also check TRM for the [Table 17: Possible Clock Sources for System Clocks],
extperiph* clock sources is PLLP_OUT, and use divider for the clock.