Regarding to external pullup on TPD12S016,my customer is asking a question.
Is this device supported external pullup at A-Port?
They confirmed it with following test but A-Port output doesn’t satisfied low level
Pull up voltage：3.3V , B-Port input : low
･A-Port output : 2.16V @Pull up =1Kohm
sink current :（3.3-2.16）/0.9k=1.254mA
･A-Port output : 0.84V @Pull up =10Kohm
sink current :（3.3-0.84）/5k=0.432mA
I understand the sink current is 3mA at 0.4V output from datasheet page17(below).
I’m wondering why drive current is low.
“CMOS/NMOS open-drain capable of sinking 3 mA of current at 0.4 V will have an output resistance of 133 Ω or less (R = E / I).”
If external pullup is not supported on this device, do you have device of supporting external pullup for level shifter on DDC line?
Or do you have another solution?