In recent years, there has been a trend in the industry to package several chips together to improve integration and reduce the final package size. The lithium-ion battery protection market is no exception. Two lithium-ion battery protection methods, A and B, appear to integrate two chips into one, but in reality, the controller IC and switching transistor chips inside the package are still separate and come from different manufacturers. This method simply combines the two into one package, commonly known as "two-in-one".
The XB430X series chips have a very high degree of integration, integrating not only the traditional control IC and switching transistors, but also resistors R1 and R2 in schematic 1 onto the same chip. The integrated chip is very small, with the smallest available in the commercially available SOT23-5L package. The switching transistors in this series have extremely low internal resistance, with the smallest reaching below 40mΩ, comparable to the best-performing switching transistors on the market. When using the smallest SOT23-5L package, continuous charging and discharging current can reach 2.5 amps without heat dissipation issues. If the continuous charging and discharging current exceeds 2.5A, it is recommended to use the SOP8 packaged product from the XB430X series.
The XB430X incorporates all the protection functions found in traditional protection methods: overcharge protection, over-discharge protection, overcurrent protection, and short-circuit protection. Furthermore, because the control IC and switching transistor are integrated on the same chip, the control IC can continuously monitor the switching transistor chip temperature. When the chip temperature becomes too high due to prolonged use in high-temperature environments, or when the charging/discharging current exceeds the normal charging/discharging current but does not reach the overcurrent protection threshold, the over-temperature protection function will be activated to protect both the chip and the battery. Additionally, the built-in switching transistor features ESD protection, significantly improving the yield rate of the protection board and battery during manufacturing.
The XB430X's internal control IC and switching transistors are manufactured using the same process and from the same manufacturer. It uses the most mature and common packaging form, resulting in significantly higher performance than traditional methods, two-in-one methods, and positive protection methods.
Using the XB4301 series chips, the final battery protection method requires only two components, compared to five components in the traditional method. This increases the output and efficiency of each placement machine by 2.5 times. Compared to traditional methods, lithium-ion battery protection board manufacturers not only eliminate the need to purchase resistors and switching transistor chips, streamlining the resource chain, but also reduce the number of solder pads for two resistors and eight solder joints for the switching transistors during board manufacturing, thus significantly lowering the production cost of the protection board.
