Microelectronics has made progress in the development of single-cell lithium battery protection chips

Recently, the Automotive Electronics Research and Development Center of the Institute of Microelectronics of the Chinese Academy of Sciences made new progress in the research and development of single-cell lithium battery protection chips, among which the protection chip with the model DM5261 has already been mass-produced.

To ensure the safety and durability of single-cell lithium batteries, each lithium battery must be equipped with a corresponding protection chip. This chip can effectively prevent the battery from over-charging, over-discharging, charge/discharge over-current and short-circuit conditions, ensuring the normal use of the battery.

Under the support of the horizontal project of Shenzhen Desai Microelectronics Technology Co., Ltd., the Automotive Electronics Research and Development Center of the Institute of Microelectronics conducts research on the protection of overcharge, overdischarge, overcurrent, and short-circuit currents of single-cell lithium batteries. On the basis of multiple MPW tapeout tests in the early stage, the project team has overcome the difficulties of Bandgap and BIAS to form three feedback loops, such as interactive startup, ESD withstand voltage, detection accuracy, and packaging yield, and successfully developed a variety of low-power, Low-cost, high-precision single-cell lithium protection chip (structure box shown in Figure 1).

The single-cell lithium battery protection chip developed has overcharge, overdischarge, discharge overcurrent, charge overcurrent, short circuit detection, and 0V charge enable/disable functions. The chip contains multiple modules such as comparators, oscillators (frequency 1KHz) and logic circuits. It adopts a fast-start circuit design to eliminate the spike effect of the output voltage during the start-up process. The wide power supply voltage range (2V-5V) and power consumption Low, consumes 3μA (VDD = 3.9V, typical) in operating mode, 0.1μA maximum (VDD = 2V) in sleep mode, and core specifications such as detection accuracy, detection range, and power consumption exceed those of similar international products. The results have been applied for invention patents, with independent intellectual property rights.