
HDMI signal-conditioning IC offers transmission line ESD protection for HDMI transmitters
Designed for home entertainment systems, such as set-top boxes, standard-definition (SD) and high-definition (HD) DVD players, Blu-ray players and A/V switches, the IP4786 also features low power consumption in standby mode, making it ideal for mobile applications such as portable media players, notebooks and tablets, game consoles, mobile phones, and digital camcorders and cameras.
The HDMI TMDS signals are protected by a new Transmission Line Clamping architecture that provides lower peak clamping voltages during electrostatic discharge. “Zero-clamping” buffers on the control lines completely isolate these signals from an ESD strike. All 13 signal lines are rated for ±8 kV in accordance with the IEC 61000-4-2, level 4 standard, as well as the 5-V power source pin. In addition, the IP4786CZ32 is the only solution to incorporate an overcurrent limiting 5-V LDO, conforming to the HDMI 1.4 requirement for overcurrent protection.
The TLC protection architecture integrates impedance-matching inductors along with the ESD protection device, providing matched 100 ohm differential impedance through the device. Unlike traditional shunt ESD devices which require board-specific external compensation, the IP4786CZ38 does not require any additional adjustment to the PCB layout, and impedance is independent of the PCB board stackup. The buffers on the control lines are the industry’s first solution that provides voltage level translation on both high and low logic levels. The buffers also enable long-cable support by overcoming the slow signal rise times associated with long cable lengths.
The IP4786CZ32 was designed to provide the fewest components and smallest board footprint of any HDMI signal conditioning and protection solution. Eliminating up to 29 discrete components, the IP4786CZ32 also reduces the required footprint by 60 percent, compared with alternative integrated solutions.
The IP4786CZ32 signal-conditioning device is available immediately from NXP and major distributors, with recommended pricing of US $1.20 in quantities of 1,000.
Visit NXP Semiconductors at www.nxp.com.