LVDS and eDP are both video signal interfaces used to connect touch screens in POS terminals, with the type of interface largely depending on the LCD manufacturer’s design.
LVDS technology appeared earlier. The interface uses the base voltage swing (about 350mV) to transmit data through bifurcation on two PCB traces or a pair of flat cables, that is, a low voltage differential signal, also known as TIA/EIA-644. If the POS terminal screen signal interface is LVDS, it means that video signals can be transmitted at a rate of several hundred Mbit/s. Due to the use of collateral and low current driving methods, low noise and low power consumption can be achieved.
However, due to the longer development history of LVDS and its limited bandwidth, display details and image clarity may be lower.
eDP, a fully digital interface based on the DisplayPort architecture and protocol, uses simpler connectors and fewer pins to transmit high-resolution signals, such as UHD/4K or higher. Additionally, eDP can carry video, audio, and touch signals through a single cable, supporting simultaneous transmission of multiple data types. With a higher transmission rate than LVDS, eDP also connects the POS terminal display to the motherboard without needing additional components, which can help reduce costs.
If the POS terminal screen resolution is 1920×1080, an LVDS interface would require 20 pairs of data transmission lines, whereas an eDP interface would need only two. In recent years, as POS software increasingly inclined to high-definition screens, POS terminal hardware manufacturers are more likely to use the eDP interface.