AITO M9 Headlight Driver Board Teardown

This article tears down the left-side headlight driver module from a high-spec AITO M9, to see exactly which key chips make up its hardware architecture.

Teardown

The teardown process was anything but smooth. This kind of automotive-grade module has glue-sealed joints and a rugged structure. After some brute-force effort, we finally managed to extract the complete internal PCB. Let's focus on the chips on it.

First, the front side of the PCB. The layout is clear, with well-defined functional zones, mainly including:

- Diodes Incorporated N-channel enhancement-mode MOSFET, model DMTH6016LFVWQ
- Panjit Automotive-grade Schottky diode, model MBR8H120PC-AU_R2_000A1
- Diodes Incorporated N-channel enhancement-mode MOSFET, model DMTH8008LPSQ
- Diodes Incorporated N-channel enhancement-mode MOSFET, model DMTH43M8LPSQ
- Texas Instruments Synchronous four-switch buck-boost converter, model TPS55288-Q1, with I²C interface control
- Texas Instruments CAN FD transceiver, model TCAN1044-Q1
- Texas Instruments Stepper motor driver, model DRV8889-Q1, one of the core components essential for AFS headlights

The back side of the PCB is a different world — the LED driver array and main control unit.

The main components include:

- NXP LED driver, model ASL2507SHNY, a two-phase boost converter responsible for boosting the battery voltage to the high voltage required by the LED strings
- NXP LED driver, model ASL3417SHNY, an automotive-grade multi-channel LED driver where each channel supports independent PWM dimming, and with a high-speed communication protocol, it can control the on/off state of LEDs in corresponding zones
- Texas Instruments Diode controller, model LM74800-Q1, an automotive-grade product mainly used in the power input stage of automotive electronic systems, providing reverse battery protection and overvoltage protection for downstream circuits
- Texas Instruments Dual-channel intelligent high-side switch, model TPS2HB35BQPWPRQ1, controlling the on/off of external power supplies
- NXP Automotive-grade MCU, model S32K312HMS, this MCU is quite powerful — an automotive-grade MCU based on the Arm Cortex-M7, responsible for running the light control algorithms and receiving commands from the body domain controller
- NXP SBC chip, model UJA1169AXF, an automotive-grade chip that highly integrates a CAN FD transceiver, power management, watchdog, and safety functions
- Nexperia PNP bipolar transistor, model PBSS5350X
- Texas Instruments CAN FD transceiver, model TCAN1044-Q1

Interestingly, this is in stark contrast to the "localized" landscape we saw when we previously tore down the front headlight driver board of the AITO M7. The M7's solution used quite a few domestic components, whereas the core chips on this M9 driver board are almost entirely dominated by Texas Instruments and NXP. Only some diodes and MOSFETs come from Diodes Incorporated, Panjit, and Nexperia — among which Diodes Incorporated and Nexperia, though international brands, have some production lines linked to domestic sources, while Panjit is a Taiwanese manufacturer.

Summary

Why did the AITO M7 still have a fair number of domestic chips, while the higher-end M9 adopts almost exclusively major international vendors? In my view, there are several possible reasons. First, higher performance and reliability requirements: NXP's ASL3417 series and TI's DRV8889 series are mature solutions verified by years of market use, especially in multi-channel independent dimming and micro-stepping motor control. Second, automotive qualification and supply stability: TI and NXP have decades of deep roots in automotive electronics, with comprehensive AEC-Q100 certification coverage. For a flagship NEV model, OEMs tend to prefer mature solutions with lower risk. So, do you think the AITO M9's choice of major international vendors is driven by performance necessity, or is it a conservative and safe bet?