About HDMI_CEC level shifting on NX development board


On NX module, HDMI_CEC is a open drain bidirectional port in 1.8V power domain. On the development board, in the CEC level shifting & blocking section, there is a 162k resistor labeled R62 pulled up to 3.3V. So I think the value of R62 should be bigger enough. But, why 162K? Or only because it’s just on the shelf?


It is under checking, will update once available, thanks.

HDMI spec requires 27kohm pull up on CEC, so we have a 162k and a 32.4k pull up on either side of the FET, to create 27k in parallel.

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