The designer needs to consider the requirement for the HDMI Transmitters Hot Plug Detect (HPD) scheme. If it is a requirement, then the V_IH of HPD on the core scalar chip is the minimum voltage needed to detect a Hot Plug event. The minimum voltage requirement is V_{5V_SUPPLY} — V_{DROP_MAX} — V_{DROP_SYSTEM} — V_{ON_MAX} > V_IH ⇒ V_{5V_SUPPLY} > V_IH + V_{DROP_MAX} + V_{DROP_SYSTEM} + V_{ON_MAX} ; where V_{DROP_MAX} is the maximum voltage drop across TPD12S521's current limiter, V_{DROP_SYSTEM} is the voltage drop across the path from Pin 38 of TPD12S521 through the sink and back to Pin 20, and V_{ON_MAX} is the maximum voltage drop across TPD12S521's level shifting NFET when ON. Otherwise, TPD12S521 is a passive ESD protection device and there is no need to power it.