DVI and HDMI interface ESD protection, DDC/CEC buffering, hot plug handling and backdrive protection

The IP4787CZ32 is designed to protect High-Definition Multimedia Interface (HDMI) receiver interfaces. It includes HDMI 5 V power management, Display Data Channel (DDC) buffering and decoupling, hot plug drive, backdrive protection, Consumer Electronic Control (CEC) buffering and decoupling, and ±12 kV contact ElectroStatic Discharge (ESD) protection for all external I/Os, exceeding the IEC 61000-4-2, level 4 standard.

The IP4787CZ32 incorporates Transmission Line Clamping (TLC) technology on the high-speed Transition-Minimized Differential Signaling (TMDS) lines to simplify routing and help reduce impedance discontinuities. All TMDS lines are protected by an impedance-matched diode configuration that minimizes impedance discontinuities caused by typical shunt diodes.

The 5 V power management enables host access to the [Extended Display Identification Data (EDID)] memory even if no HDMI plug is connected. The overall load to the 5 V line is according to the HDMI requirements.

The DDC lines use a buffering concept which decouples the internal capacitive load from the external capacitive load for use with standard Complementary Metal Oxide Semiconductor (CMOS) or Low Voltage Transistor-Transistor Logic (LVTTL) I/O cells down to 1.2 V. This buffering also redrives the DDC and CEC signals, allowing the use of longer or cheaper HDMI cables with a higher capacitance. The internal hot plug drive module simplifies the application of the HDMI receiver to control the hot plug signal.

All lines provide appropriate integrated pull-ups and pull-downs for HDMI compliance and backdrive protection to guarantee that HDMI interface signals are not pulled down if the system is powered down or enters Standby mode. Only a single external capacitor is required for operation.