I. Overview

In modern display systems, data exchange between the host controller chip and the display panel is of paramount importance. Currently, the industry’s mainstream display interfaces include RGB TTL, LVDS, and MIPI DSI. The fundamental differences among these three interfaces lie not only in the signal types at the physical layer—such as TTL levels versus low‑voltage differential signaling—but also in the signal content and protocol mechanisms employed at the link layer. This paper aims to systematically compare the technical distinctions between MIPI DSI and LVDS, providing a professional reference for the company’s product development, hardware selection, and customer communication.

II. Comparison of Core Differences

The core differences between MIPI DSI and LVDS are primarily reflected in the following two dimensions:

Richness of transmitted content: The traditional LVDS interface serves primarily as a physical-layer transmission medium, focusing on the transport of video pixel data. In contrast, MIPI DSI is a complete protocol stack that not only supports high-definition video streams but also allows control commands—such as screen initialization, backlight adjustment, and sleep/wake operations—to be embedded directly within the link, achieving a high degree of integration between data and control.

Protocol Mechanisms and Handshake Rules: The LVDS interface primarily converts the RGB TTL signals output by the host controller into serial data according to standard formats such as SPWG or JEIDA, making it a relatively “transparent” transmission channel. In contrast, MIPI DSI adheres to stringent protocol specifications, transmitting video streams and control data via a defined handshake sequence, packet encapsulation, and command rules, thereby offering greater intelligence and flexibility.

III. Analysis of LVDS Interface Technology

1. Technical Background and Advantages
In early LCD displays, the RGB TTL interface, which relied on multi‑channel ribbon cables for transmission, suffered from bulky cable harnesses, limited transmission distances, and severe electromagnetic interference (EMI), making it difficult to meet the demands of high resolution and ultra‑thin form factors. LVDS (Low Voltage Differential Signaling) was developed by National Semiconductor (NS) specifically to address these challenges. By employing a low voltage swing of approximately 350 mV, LVDS enables high‑speed serial transmission over differential pairs or balanced cables, offering significant advantages such as low noise, low power consumption, strong immunity to interference, and long‑distance transmission.

2. Circuit Composition and Operating Principle
The LVDS interface circuitry consists primarily of an “LVDS transmitter” on the driver board side and an “LVDS receiver” on the LCD panel side. The transmitter converts the parallel RGB TTL signals output by the main controller—along with line‑sync, field‑sync, pixel clock, and other timing information—into low‑voltage serial LVDS signals, which are then transmitted to the panel via a flexible flat cable (FFC). The receiver subsequently reconverts these signals back into parallel TTL format and feeds them to the LCD panel’s timing controller (T-Con) and row‑and‑column drive circuits. In both the data and clock channels, LVDS employs differential signal pairs with positive and negative voltages to maximize common‑mode noise rejection.

IV. Technical Analysis of the MIPI DSI Interface

1. Alliance Background and Positioning
MIPI (Mobile Industry Processor Interface) is an open standard jointly initiated by industry giants such as ARM, Nokia, and TI, designed to provide low-power, high-bandwidth interconnect solutions for mobile application processors. In the display domain, MIPI DSI (Display Serial Interface) has become the dominant interface in high-end devices like smartphones, tablets, and automotive infotainment systems.

2. Protocol Architecture and Packet Mechanism
MIPI DSI employs a layered protocol architecture, with the packet design of its lower-layer protocol (LLP) serving as its key highlight. LLP packets exhibit the following characteristics:

Flexibility and Integrity: Supports the transmission of data of any type; each packet includes a start-of-frame delimiter (SoT) indicating the beginning of transmission and an end-of-frame delimiter (EoT) marking its conclusion, along with a 16-bit error-checking code to ensure data integrity.

Multi-channel and multi-format: Supports 8-bit data depth, provides four virtual channels, and each packet explicitly identifies the data type, pixel size, and format.

Combination of long and short packets: Data packets are categorized into long packets—used to transmit large volumes of video pixel data—and short packets—used to carry control commands—enabling efficient multiplexing of video and control signals over the same physical link.

V. Summary and Selection Recommendations

LVDS interface: Mature technology, low cost, and strong anti-interference performance, making it well suited for industrial displays, conventional automotive applications, and medium- to large‑size LCD panels that are cost‑sensitive, require moderate resolution (e.g., 1080p or lower), and do not necessitate complex control commands.

MIPI DSI interface: boasts extremely high bandwidth, ultra-low power consumption, support for high resolutions (2K/4K) and high refresh rates, and robust control‑command interoperability. It is well suited for smartphones, high‑end tablets, AR/VR devices, and next‑generation smart terminals with stringent requirements for thin form factors and low power.

In practical engineering applications, the R&D team must comprehensively evaluate and select the most suitable display interface solution based on the target product’s resolution requirements, power‑consumption budget, host‑controller chip platform, and system complexity.