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osresearch / pixel-wrangler

HDMI to whatever adapter
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i2c needs 5v protection #27

Open osresearch opened 1 year ago

osresearch commented 1 year ago

as part of the v0 board issues (#22), the i2c line needs a level shifter. It is weakly pulled to 5v on the HDMI source side, which could damage the FPGA that is pulling it high to 3.3v.

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the TI TPD12S016 "HDMI Companion Chip" is a single chip device that also adds ESD filtering so it might be worth spending the $0.80 each to add to the BOM. As a plus, the pinout matches the HDMI port, so hopefully it is a "drop in" with a slight tweak to the board size.

osresearch commented 1 year ago

although this comment says it can't be used as an HDM sink due to pullup resistors, although they don't provide any altneratives. https://e2e.ti.com/support/interface-group/interface/f/interface-forum/458493/tpd5s116-used-as-hdmi-sink