Design Of LCD Driver Interface Based On MIPI-DSI Protocol

MIPI-DSI is a high-speed, low power dissipation serial interface proposed by the MIPI Alliance for mobile devices, which can meet the requirements of high-resolution display and less power consumption of display module.This paper presents a kind of LCD driver interface for VGA format based on DSI protocol. The interface consists of physical layer, lane-manager layer, protocol layer and application layer. The circuit in physical layer is responsible for controlling switch between high-speed mode and low-speed mode and the bus arbitration, as well as receiving and transmitting serial data. The timing of handshake block is reconfigured to improve the flexibility of handshake. This paper consider that Line_code function is not essential and it can be simplified, so that the speed and bandwidth utilization of high-speed module is improved. Segmenting the clock domains corresponding to each module, to ensure high-speed part is working reliably. Lane-manager layer circuit is used for merging the two channels of data, introduces an external clock but no extra glitches, and the follow-up operation can continue when the clock signal from the host side is disappearing. Protocol layer circuit is responsible for packing and unpacking data packets, including ECC and CRC checking. Reduce the ECC circuit area and ensure a consecutive data stream processing, without introducing a pipeline. Propose a new implementation with parallel computation to calculate checksum and increase the overall processing speed of bytes instead of using high-speed clock. Application layer circuit is in charge of sending the unpacked data to LCD Driver in the fomat of DBI or DPI, and read the parameters in requirement. Add DCS instruction into command decoder block and widen the application to read and write commands or parameters but not limit to DSI commands.In this design, Verilog HDL is used for RTL-level description of interface architecture as well as each module. A simulation platform is build of the inteface circuit and two modules which are set up to simulate the behavior of DSI host and LCD driver, to test interface circuit with the help of a simulation software Modelsim. The result shows the interface pass the functional verificationDesign is compiled with smic 0.13 library by synopsys DC, and it will take up 85418.4115μm~2 and consume 5.243mW with the highest frequency of 500MHz. And verification on design after compiled is taken by Modelsim. The simulation result and the DC report shows the design achieves the desired objectives.