NXP has reportedly introduced a new battery junction box IC, which is a key component for battery pack monitoring in electric vehicles. It is reported that this is the first battery junction box to integrate all the basic battery packs and functions into a single chip. The IC is part of the Battery Management System (BMS) that ensures the safe and efficient operation of the battery pack by accurately measuring the voltage, current, and temperature of the battery cells.
Dubbed the MC33774, the IC is an 18-channel analog front-end device capable of cell measurement accuracy as low as 0.8 mV over a wide temperature range. While traditional battery pack-level monitoring systems require multiple individual components, external actuators and processing support, NXP's new MC33777 integrates key BMS functions. The integrated circuit dramatically simplifies OEM design complexity, certification, software development effort, and cost, while also optimizing the overall performance of the system. In addition, MC33774 supports functional safety level ASIL-D, which is particularly suitable for high-voltage lithium-ion batteries, which are closely related to safety, and can make full use of the usable capacity. It also features an on-board passive battery balancing function that automatically selects the optimal balancing sequence, effectively improving the overall efficiency and service life of the battery pack.
MC33774 uses NXP's SmartMOS SOI (Insulating Silicon Wafer) technology to provide battery measurement accuracy down to ±0.8 mV, helping to ensure the lifetime performance of battery chemistries such as nickel-manganese-cobalt (NCM) and lithium iron phosphate (LFP). In addition, MC33774's precision design and calibration technology can save customers the cost of end-of-line inspection (EOL) calibration.
Figure: NXP MC33777 (Source: NXP)
This innovative integrated circuit continuously monitors the battery current and slope at intervals of eight microseconds, thus ensuring that the high-voltage battery is protected from overcurrent. It can also analyze and respond to a wide range of customizable events up to 10 times faster than traditional integrated circuits, e.g., without the need for a specified current threshold. MC33777's fuse emulation technology dramatically reduces costs for OEMs and Tier 1 suppliers by eliminating costly and unreliable blown fuses in the system. This, in turn, improves reliability and enhances passenger safety. For OEMs, simplicity is a major advantage. MC33777 integrated circuits (ICs) reduce the number of components by 80 percent, reducing the necessary printed circuit board (PCB) area and minimizing the software development effort required for hardware implementation. As a result, the adoption of NXP's latest battery junction box ICs can help speed up design cycles and reduce the time it takes to bring the next generation of electric vehicles to market.
For the end consumer, MC33777 faster response times mean greater safety. For example, the risk of electric shock to passengers is reduced in the event of a collision, and the precise measuring range also extends the range.
NXP also offers a complete 800V HVBMS reference design kit that includes a battery management unit (BMU), a cell monitoring unit (CMU) and a battery junction box (BJB), as well as software drivers and an extensible set of functional safety documentation. These design resources help accelerate the customer's product development process and ensure the safety and reliability of the system.
The introduction of this new battery junction box IC and related products further strengthens NXP's leadership position in EV battery management system solutions, providing EV manufacturers with a more efficient and safer product option.
