Introduction of industrial LCD display interface

二： LVDS interface

(1) interface definition

LVDS：It is Low Voltage Differential Signaling, is a low voltage differential signaling technology interface. It is a kind of digital video signal transmission mode developed by American NS company to overcome the disadvantages of large power consumption, large EMI electromagnetic interference and so on when transmitting wideband high rate data at TTL level.

The LVDS output interface uses very low voltage swings (about 350mV) to transmit data through differential data on two PCB lines or a pair of balanced cables, that is, low voltage differential signaling. Using the LVDS output interface, can make the difference in the PCB signal line or cable to balance the transmission rate of hundreds of Mbit/s, due to the low voltage and low current drive mode, thus achieving low noise and low power consumption.

(2) interface type

A. 6 bit LVDS output interface

This interface circuit uses single mode transmission, each primary color signal uses 6 bit data, a total of 18 bits of RGB data, therefore, also known as 18 bit or 18bit LVDS interface.

B. dual 6 bit LVDS output interface

The interface circuit, the dual mode of transmission, each primary signal using 6 bit data, the frontage road data for the 18, even the way the data is 18, a total of 36 bit RGB data, therefore, also known as 36bit 36 or LVDS interface.

C. single channel 8 bit LVDS output interface

This interface circuit uses single mode transmission, each primary color signal uses 8 bit data, a total of 24 bits of RGB data, therefore, also known as 24 bit or 24bit LVDS interface.

D. Dual 8 bit LVDS output interface

The interface circuit, the dual mode of transmission, each primary signal using 8 bit data, the frontage road data for the 24, even the way the data is 24, a total of 48 bit RGB data, therefore, also known as 48bit 48 or LVDS interface.

(3) interface characteristics

A. high speed (general 655Mbps)

B. low voltage, low power, low EMI (swing 350mV)

C. has strong anti-interference ability and differential signal

(4) resolution

A. single way: 1280*800@60

1366*768@60

B. dual Road: 1920*1080@60

(2) MIPI characteristics

A. high speed: 1Gbps/Lane, 4Gbps throughput

B. low power consumption: 200mV differential swing, 200mV common mode voltage

C. noise suppression

D. less pin, PCB layout is more convenient

(3) resolution

MIPI-DSI:2048*1536@60fps

(4) MIPI-DSI mode

A. Command Mode

Corresponding to the parallel interface with MIPI-DBI-2, Frame Buffer, DCS Command Shuabing set based on similar to the CPU screen.

B. Video Mode

Corresponding to the parallel interface MIPI-DPI-2, Shuabing based on timing control, similar to the RGB synchronous display

(5) working methods

A. command mode of operation

Use DCS Long Write Command Packet to refresh GRAM.

The first packet of each frame is write_memory_start DCS, and each frame is synchronized with command.

B. video mode of operation

The use of sync packet Pixel packet LCD to achieve timing synchronization, shuabing. The blank space can be arbitrary, ending at LP per frame.