How to test HDMI Cable and Display Port Cable

Due to the complexity, the high demands on accuracy in production and the high production costs, the professional testing of HDMI cables is a necessity.

How is an HDMI cable constructed?

Each HDMI plug or connector has 19 pins (contacts). The contacts connect the digital signals of the master (example: game console) through the internal lines of the HDMI cable with those of the slave (example: television).

Pins 1-9 are the connection of the TDMS channels, which each occupy 3 pins. The TDMS channels are the channels that enable the transmission of digital electronic signals and that contain audio and video information.

Contacts 10 to 12 are provided for the synchronization of the signals (clock), these are referred to as TMDS clock channel.

Contact 13 transmits the CEC channel (Consumer Electronics Control), which sends commands between the connected devices and controls them.

Contact 14 currently has no function, it is reserved for future use scenarios and ensures that the HDMI standard remains expandable.

The contacts 15 and 16 are referred to as a screen data channel, also called a DDC (Display Data Channel). Information is exchanged between the connected devices using EDID (Extended Display Identification Channel).

Contact 17 is a data shield for the CEC and DDC channels, while contact 18 is responsible for the power supply (+ 5 volts).

Contact 19 is referred to as hot plug detect, which detects whether a device is switched on or off or whether the HDMI cable is plugged in or unplugged. A "hot connection" ;-)

Special features of an HMDI cable

HDMI cables are always backwards compatible. In practice, this means that, for example, a television set that works with HDMI 1.2 or HDMI 1.3 can also be operated with an HDMI 1.4 cable without any problems. The biggest difference in quality between cheap and expensive HMDI cables is the shielding, which ensures that the signal integrity is not compromised.

Tool for testing HDMI cables

Total Phase's Advanced Cable Tester can reliably test HDMI Type A to HDMI Type A cables. The cable tester checks for all important parameters and influencing factors that can affect the quality of the HDMI cable.

The test spectrum includes:

Short test - Dynamic visualization of the test results
Open testing - Dynamic visualization of test results
Continuity test - dynamic visualization of test results
DC resistance measurement for most wires with milliohm accuracy on ground and power cables, ohm resolution on most other wires, continuity testing only on high speed data lines
Signal integrity test of data lines with 12.8 Gbit / s per channel
E-marker review
Call / function of the lightning plug (Apple Lightning Cables) *
Surge Protection (Apple Lightning Cables) *
Voltage recovery test (Apple Lightning Cables) *
Quiescent current consumption (Apple Lightning Cables) *
as well as testing the shield