From 2017 to 2020, China's motorcycle production and sales remained steady at around 17 million units annually. In 2021, as motorcycle companies aggressively expanded into international markets, export activities surged, driving production and sales to 17.52 million and 19.48 million units, respectively. By the end of 2022, China's motorcycle exports continued to grow, with 35 million units exported, valued at USD 12.317 billion, cementing China's position as a global leader in motorcycle production and exports. China plays a significant role as an innovator in the worldwide motorcycle market.

In recent years, increasing environmental awareness and global carbon reduction policies have prompted traditional motorcycle companies to enter the electric vehicle sector, accelerating the trend towards electric motorcycles. In 2021, several leading motorcycle companies established new energy brands and actively developed new energy products. For instance, CFMOTO launched a new electric model under its "ZEEHO" AE8 brand in early 2022, and Qianjiang Motorcycle's Shanghai company began operations at the end of 2021, setting a new course for Qianjiang's future in new energy two-wheelers. The motorcycle industry is rapidly moving into the new energy "blue ocean," further advancing the industry's development. Statistics show that in the first quarter of 2022, fuel-powered motorcycles accounted for 83.2% of sales, while electric motorcycles accounted for 16.8%. The market share of electric motorcycles is rapidly increasing and is expected to become a mainstream trend.

The Chinese government issued the mandatory national standard GB24155—2020, "Safety Specifications for Electric Motorcycles and Electric Mopeds," to regulate the electric motorcycle market and products on May 29, 2020. From the implementation date of this standard, new electric motorcycle and moped products applying for certification must comply with GB24155—2020 standards. The GB24155-2020 standard includes several requirements for battery safety, electric shock protection, operational safety, and safety markings.

Traditional fuel motorcycles are widely utilized worldwide due to their versatility in various environmental conditions, spanning from cold to hot climates. They can navigate urban roads and rugged terrains with rain, snow, and extreme heat. They are known for their high stability, long endurance, and excellent maneuverability. Motorcycle users naturally expect electric motorcycles to inherit these characteristics. While traditional fuel motorcycles incorporate electronic control units like ABS, closed-loop fuel injection, and dashboards, their primary reliance is on mechanical structures. In contrast, electric motorcycles are built on electrical systems comprising motors, batteries, and electronic controls, which face electrification challenges such as fluctuating environmental temperatures, limited installation space, voltage spikes during rapid acceleration or deceleration, and complex electrical conditions arising from multiple electronic control units during operation.

In 2021, Nuvoton Technology launched the next-generation industrial-grade AFE products, KA49517A/KA49522A, specifically designed to address these electrification challenges.

AFE (Analog Front End) products play a crucial role as core components of battery management systems, providing precise measurement and continuous monitoring of battery voltage, current, temperature, and other critical parameters. The characteristics of AFE products significantly impact the overall control performance of battery management systems.

Nuvoton's industrial-grade AFE products are designed with three core principles: safety, simplified design, and compatibility.

【Safety】

The chips leverage the industry-leading SOI (Silicon On Insulation) high-voltage process for AFE products, incorporating multiple diagnostic modules to enhance operational safety.

Nuvoton has advanced its SOI process to 144V, the highest in the battery AFE industry. The SOI process ensures more significant safety margins for AFE chips, enabling them to withstand abrupt voltage fluctuations. Additionally, SOI utilizes insulation layers and channel processes to isolate functional modules, effectively preventing parasitic latch-up, minimizing high-frequency noise and leakage currents, and enhancing chip stability under complex electrical conditions.

Built-in diagnostic modules at the system level prevent various battery system abnormalities.

【Simplified Design】

The chip integrates multiple functional modules required for battery systems (such as voltage, current, temperature measurement, battery balancing, charge and discharge control, and safety diagnostics), realizing an All-In-One single-chip system. The diagram below shows that only a few peripheral components are needed to achieve high precision and stability in battery management systems based on Nuvoton's KA49517A/KA49522A. Additionally, the compact size of the HQFP64 (10mm x 10mm) chip facilitates miniaturization.

【Compatibility】

Unified measurement accuracy and pin-to-pin design enhance system compatibility and standardization. KA49517A/KA49522A, designed with high cell count and pin-to-pin compatibility, effortlessly supports a 48V ~ 72V single-chip battery management system platform. This simplifies early-stage system platform design and later-stage production/materials management, effectively reducing system costs.

Nuvoton's innovative technology ensures consistent measurement accuracy across a broad temperature range (as illustrated below). This capability enables battery systems to adapt to diverse environmental conditions and simplifies system design's complexity.

Nuvoton has launched the KA49517A and KA49522A based on the chip design principles outlined above, incorporating the following significant features:

Battery Monitoring Channels and Power Voltage:

⚫ Supports 17 channels (KA49517A) / 22 channels (KA49522A) for serial battery connections

- Power range: 12.5V to 85V (KA49517A) / 12.5V to 110V (KA49522A)

- Maximum withstand voltage: 130V

ADC Acquisition:

⚫ Built-in 14-bit ADC for voltage acquisition from 0V to 5V

- Voltage accuracy: typ: ±5mV; max ±10mV

- Accuracy conditions: voltage range 2.0V to 4.3V; temperature range -30°C to +65°C

⚫ Built-in low-speed 16-bit ADC for Coulomb metering

⚫ Built-in high-speed V-I synchronous 15-bit ADC

⚫ 5 temperature acquisition channels

High-side MOSFET Driver:

⚫ Charging (CHG) and discharging (DIS) N-MOSFET high-speed drivers with built-in charge pump (Cload=20nF; Ton=50us; Toff=30us)

⚫ 2 high-end P-MOSFET drivers (GPOH)

Operating Modes:

⚫ Supports multiple operating modes (Active/Low Power/Standby/Sleep/Shutdown)

⚫ Charger detection, load detection, and low-current detection with MCU interrupt capability

Safety Protection Features:

⚫ Comprehensive self-diagnostic safety protection

⚫ Secondary fuse protection for controllable fuses

⚫ Autonomous cutoff protection for charge and discharge (CHG&DIS)

⚫ Overcurrent and overvoltage built-in alarm interrupts (ALARM)

Other Features:

⚫ Up to 1 MHz SPI communication interface supporting CRC check and watchdog timer

⚫ 3 GPIOs

⚫ Built-in balance MOSFET (also supports external balance MOSFET)

⚫ LDO voltage regulator (REGEXT): configurable as 5V/3.3V/2.5V (50mA)

⚫ Package: HQFP064-P-1010 (10mm2, 64 pins) (pin pitch=0.5mm)

As electric motorcycle applications grow, Nuvoton introduces additional industrial-grade AFE products alongside KA49517A and KA49522A to support electrification. For more information, please visit our official website.