Amidst the wave of automotive electrification and intelligence, headlights have long surpassed their original function of "illuminating the front", becoming a crucial medium for perception and interaction. As the flagship model of a new force in automobile manufacturing, the NIO ES8's iconic split headlights are not only a finishing touch in design but also a culmination of technology. The officially claimed "intelligent multi-beam headlights" coupled with LiDAR can achieve precise anti-glare, so in this issue, we will disassemble the drive control board of this headlight to see how its hardware solution is actually constructed?

Disassemble

The appearance of the ES8 headlight drive control board is basically the same as the previously disassembled headlight drive board, with nothing particularly special about it. If I had to point out something unique, my first impression might be that it looks a bit better. After disassembly, there is only one PCB board inside, with a lot of thermal grease connecting the capacitors and inductors to the housing for heat dissipation. Let's take a closer look at some of the main chip information.

The control chip is a 32-bit automotive-grade microcontroller from NXP, model FS32K146HAMLL. It is a high-real-time MCU whose primary task is to translate the instructions from the domain controller into specific currents, timings, and fault diagnosis, ensuring absolute control stability. After all, the core of any automotive-grade controller is safety first, followed by functionality. On this side of the PCB board, besides the main control chip, other components are mainly capacitors and inductors. It's quite striking how aesthetically pleasing and visually appealing this PCB layout is. This PCB layout engineer is quite interesting.

Next, let's look at the components on the back of the PCB board. Some diodes will not be introduced separately, and we will focus on functional components.

Four NXP automotive-grade multi-channel LED drivers, model ASL3417SHNY, are likely responsible for the independent switching and PWM dimming of matrix LED pixels. These chips communicate with the MCU through a high-speed SPI interface to control each LED.

Two N-channel MOSFETs from ON Semiconductor, model NTMFS015N10MCLT1G. This is an N-MOSFET with a voltage rating of 100V and extremely low on-resistance. In high-frequency switching scenarios such as LED driving, low on-resistance means lower heat generation.

NXP's dual-phase boost converter, model ASL2507SHNY, is essential for addressing the issue that LED modules require constant current driving, and the input voltage is often lower than the series voltage drop of LED beads (especially when multiple LEDs are connected in series). This chip is specifically designed to solve this problem. Moreover, the dual-phase design is also a highlight: it not only reduces the stress on the single MOSFET but also effectively minimizes input ripple. Additionally, this chip features an ultimate failsafe design - if SPI communication is lost or the MCU crashes, it will automatically switch to a preset safe mode, keeping the low beam lights on to prevent sudden blindness during nighttime driving.

Three NXP CAN transceivers, model TJA1044GT/3, feature a very compact package. These chips enable CAN network transmission throughout the entire vehicle and possess strong common mode rejection capability, ensuring no data loss in noisy electrical environments. Additionally, they support local wake-up functionality - when there is a specific message on the CAN bus, it can wake up the sleeping SBC and main MCU, enabling rapid response throughout the vehicle.

Why is a stepper motor driver needed in headlights? It's quite simple: it's for the mainstream adaptive headlamp system.

Infineon's intelligent high-side power switch, model BTS7040-2EPA, serves to replace traditional relays and fuses, providing intelligent power supply for various auxiliary loads inside the headlights. Due to its current detection function, the MCU can monitor in real-time whether the load is open or short-circuited, thus achieving self-diagnosis.

Infineon's P-channel power MOSFET, model IPD90P04P4L-04; and Avago's N-channel power MOSFET, model NTD3055L104T4G.

Infineon's SBC chip, model TLE9263-3BQX, not only manages power but also integrates a CAN transceiver, watchdog, and wake-up logic. Even when the main MCU is in hibernation, it can monitor wake-up events, which is crucial for power consumption management in electric vehicles.

BOM list of main components: