The era of the multi-screen car cockpit has arrived

Sitting in the cockpit of Tesla’s latest Model 3, chances are you’ll be drawn to the 15-inch touch screen in the center of the cockpit even before starting the motor. Replacing the dashboard and central control in the traditional cockpit, the touch screen eliminates the need for almost all physical buttons, endowing the entire cockpit with a minimalist, futuristic ambiance.

 

Touch screens in the car cockpit are nothing new, but the extent to which the touch screen has been used in the Model 3 is unprecedented and indicative of a major and disruptive trend. Touch screens are becoming the norm for in-vehicle HMI, and in the future, larger and more numerous screens will appear in the cockpit. According to forecasts by analysts at Strategy Analytics, the number of displays may reach or even exceed 10 in certain luxury cars of the future.

 

 

There are a few factors driving the rise of the multi-screen. They are: 

 

First of all, to ensure a safer and more comfortable user experience, today's cars need to process a large amount of data. The information related to this data must also interact with the user more efficiently. Obviously, traditional "instrument panel + central control" vehicle-mounted HMI cannot offer this kind of information interaction, and moreover the way in which the information is displayed is not exactly user-friendly. The only solution is greater numbers of larger and more intuitive touch screens.

 

Secondly, today’s car is no longer simply a means of transportation. As the carrier of ever more infotainment functions, it needs to provide personalized services to all of the users in the cockpit, including the driver and passengers. As the central control screen is obviously unable to meet the personalized needs of multiple users, multi-screen configuration is critical.

 

In addition, as information interactions between cars, users and the outside world become increasingly frequent and more diversified, multi-screen linkage with each screen performing individual duties provides a more flexible and extensible solution.

 

Of course, the iterative computing of any single function will inevitably bring new technical challenges. For example, the increased number of screens and enhanced functions within the limited space of the car pose require the electronic components behind the screen to be fully upgraded before becoming highly integrated and miniaturized. These complex and difficult challenges are already emerging and being addressed. 

 

 

"Compressing" the size of the electronic system behind multiple screens can be carried out from multiple dimensions, but the most critical point of focus is defintiely the application processor that serves as the core of screen processing control. In traditional automobile systems, the processing/controller that controls each screen is independent, which means that for each additional screen, another processing/controller needs to be added, thus adding cost and using up space. To solve this problem, you have to ask the question, "Can one processor support multiple screens?" NXP's i.MX 8QuadMax application processor is a solution designed to address this very challenge.

 

According to the information provided by NXP, i.MX 8QuadMax integrates two Arm Cortex-A72 cores, four Cortex-A53 cores, two Cortex-M4F cores and two GC7000XS/VX GPUs. It also includes HiFi 4 DSP, supports LPDDR4 Memory, and has built-in dual Gb Ethernet with audio and video bridging (AVB) function. You could say that i.MX 8QuadMax inherits the high-performance characteristics of the i.MX 8 application processor family with a GPU, four Arm cores and IO options, offering users the processing power and flexibility required by artificial intelligence and machine learning.

 

Its biggest feature is a unique hardware partition structure and function that enables it to run multiple operating systems without a management program, and support up to four independent screens on a single processor (resolution up to 4K) while providing sufficient processing performance. The codes between each screen are "isolated" from each other, thus fulfilling the unique reliability and security requirements of each screen.

 

At CES2020 at the beginning of the year, NXP demonstrated a multi-screen solution based on dual i.MX 8QuadMax chips that supports up to 11 screens. These displays include HUD, instrument panel, co-driver display, central control, left and right rear view mirror display, as well as the inner rear-view mirror, literally covering all conceivable scenarios of screen-based automotive HMI applications.

 

Currently, i.MX 8QuadMax is ready for commercial use. For example, through cooperation with global high-end in-vehicle infotainment system supplier ART, the multi-screen display system based on i.MX 8QuadMax has been incorporated into the 2021 production plans of certain high-end models. Once it has been embraced by the market, it is only a matter of time before this "one-core multi-screen" solution gradually seeps down to the middle and low-end car markets.

 

 

Aside from the main control chip, other peripheral components of the car display are also undergoing upgrades to meet the arrival of the multi-screen era. For example, "new species" have emerged in the field of power management chips for automotive displays.

 

Traditional car display power supply design requires 4-5 discrete ICs, which usually include a high-voltage buck converter providing a 3.3V power rail; a high voltage and low IQ LDO responsible for MCU power supply; a low-voltage LDO for low-noise applications; a low-voltage step-down converter providing power supply for the deserializer; and a watchdog timer supporting MCU reset (Figure 3). As the number of screens increases, this type of architecture will inevitably crowd the limited system space available.

 

To simplify the automotive display power system, in early 2020, Maxim Integrated launched the highly integrated automotive display PMIC MAX16923, which integrates five major functions in a single chip, effectively reducing design complexity and solution size. Along with the MAX20069 TFT bias power supply and LED driver, the power supply requirements of car displays of 12.3 inches and below can be met with just a simple dual-chip architecture (Figure 4).

 

 

As you can see from Figure 4, the MAX16923’s highly integrated power management functions include:

 

By adopting this solution, the number of chips in the system solution is reduced from five to one, and the size is reduced by 50%. This effectively reduces design complexity and the size of the solution while optimizing BOM cost. The space and cost savings mean that the car display system has a larger function expansion space and offers a better user experience. This brings a world of added value.

 

In short, the exciting new car cockpit experience in the emerging multi-screen era is sure to pique the interest of many new users. For developers who are keen to exploit its commercial potential, now is the time to "tweak" the chips behind the screen, upgrade iterative computing, and free up more space for multi-screen applications in the automobiles of the future.