The IP4778CZ38 is designed for HDMI receiver host interface protection. The IP4778CZ38 includes DDC buffering, slew rate acceleration and decoupling, hot plug control, backdrive protection, CEC slew rate control, optional multiplexing of DDC signals, and high-level ESD protection diodes for all HDMI signals.

The DDC lines are buffered using a new buffering concept which decouples the internal capacitive load from the external capacitive load. This allows higher PCB design flexibility for the DDC lines with respect to the maximum load of 50 pF specified in the HDMI 1.3 specification. This buffering also boosts the DDC signals, allowing the use of longer HDMI cables having a higher capacitive load than 700 pF. The CEC slew rate limiter prevents ringing on the CEC line and greatly reduces the number of discrete components needed by the CEC application. HDMI receiver and system GPIO applications are simplified by an internal hot plug driver module and hot plug control.

The DDC, hot plug and CEC lines are backdrive protected to guarantee HDMI interface signals are not pulled down if the system is powered down or enters Standby mode.

All TMDS intra-pairs are protected by a special diode configuration offering a low line capacitance of 0.7 pF only (to ground) and 0.05 pF between the TMDS pairs. These diodes provide protection to components downstream from ESD voltages of up to +-8 kV contact in accordance with the IEC 61000-4-2, level 4 standard.