由于矿井地形繁杂、光照度低，且空气中存在瓦斯、粉尘等爆炸性混合物，若操作不当，则极易引发爆炸事故，因此矿井工作现场的执法监督和安防巡检，将在矿山安全开采中发挥重大作用。而现有矿用信息记录仪在低照度环境下采集的图像清晰度较低，且仅限于录音、录像功能，由此，二次开发一款功耗低、分辨率高、安全性高且满足低照度音视频采集、传输需求的矿用本安型信息记录仪具有一定的实用意义。

本文从防爆类型、技术措施入手，分析矿用电气设备特征，总结本安电路设计流程，同时通过对比不同的解决方案，选择以模块化的思想设计并实现。首先，以本质安全为前提，从音视频采集、夜视、显示、存储等方面深入研究，提出本安型信息记录仪的设计方案：基于主动红外技术，选用集成CMOS图像传感器的N8F0101模组，利用LTR-308ALS检测光照强度，并通过LM3410驱动850 nm红外LED辅助光源，实现低照度采集功能；选用GTM2718AB381拾音器、AW87318音频放大器以及D类音频编解码器LM49350实现音频采集功能；配置低功耗、高性能的液晶彩色触摸屏和TF内存卡，实现显示、存储功能；采用单节PL853545锂电池供电，对锂电池添加电池保护板电路，利用WS3213C芯片和BQ24295芯片实现电源管理，以LTC4364为核心设计双重保护电路，并通过“Boost+Buck+LDO”的方法实现电压转换功能，以支持负载电路正常工作，从而提升供电单元的安全性。其次，利用Altium Designer设计设备的PCB版图，并添加电磁兼容性设计，增加设备稳定性。最后，对本安型信息记录仪进行性能测试和功能测试，并向国家安全矿用设备检测检验中心申请煤安检测。

测试结果表明，设备各单元电路均满足低功耗本安设计要求，具备自动红外补光功能，视频分辨率为2560´1440，全黑环境的可视距离大于10米，整体功耗小于5 W，能够实现低照度及全黑环境下的音视频采集、存储、显示、传输等功能，除此之外，设备的各项指标已满足煤安检测标准并获得相应证书。论文设备不仅可以作为执法记录仪使用，还可以配合应急救援工作，具有较高的实用价值和研究意义。

Due to the complex terrain of the mine, low illumination, and the presence of explosive mixtures such as gas and dust in the air, if the operation is improper, it is very easy to cause explosion accidents. Therefore, the law enforcement supervision and security inspection of the mine work site will play a significant role in the safe mining of mines. However, the image clarity collected by the existing mine information recorder in low illumination environment is low, and it is limited to the audio and video recording functions. Therefore, it is of certain practical significance to integrate and develop a mine intrinsically safe information recorder with low power consumption, high resolution, high security and meeting the requirements of low illumination audio and video acquisition and transmission.

Starting from explosion-proof types and technical measures, this paper analyzes the characteristics of mine electrical equipment, and summarizes the design process of intrinsically safe circuits. At the same time, by comparing different solutions, choose to design and implement with a modular approach. Firstly, based on the premise of intrinsic safety, the design method of intrinsically safe information recorder is proposed through in-depth research of audio and video acquisition, night vision, display, storage, and other aspects. The specific method is based on active infrared technology, the N8F0101 module with integrated CMOS image sensor is selected, LTR-308ALS is used to detect the light intensity, and the LM3410 drives the 850 nm infrared LED supplementary light source to achieve the low illumination video acquisition function. GTM2718AB381 pickup, AW87318 audio amplifier and Class D-audio codec LM49350 are selected to achieve the audio acquisition function. Equipped with low-power, high-performance LCD color touch screen and TF memory card to realize the display and storage functions. A single PL853545 lithium battery is used for power supply, a battery protection board circuit is added to the lithium battery. The WS3213C chip and BQ24295 chip are used for power management, and a dual protection circuit is designed with LTC4364 as the core. The voltage conversion function is achieved through the "Boost+Buck+LDO" method to support the normal operation of load circuits, thereby improving the safety of the power supply unit. Secondly, Altium Designer is used to design the PCB layout of the equipment, and electromagnetic compatibility design is added to increase the stability of the equipment. Finally, the performance test and functional test of the intrinsically safe information recorder are carried out, and applies for coal safety testing to the National Safety Mining Equipment Testing and Inspection Center.

The test results show that each unit circuit of the equipment meets the requirements of low-power intrinsic safety design, with automatic infrared light supplement function. The video resolution is 2560 × 1440, the visible distance in the fully black environment is greater than 10 meters, and the overall power consumption is less than 5 W. It can achieve the functions of audio and video acquisition, storage, display, and transmission in low illumination and fully black environments. In addition, all indicators of the equipment have met the coal safety detection standards and obtained the corresponding certificates. The equipment can not only be used as a law enforcement recorder, but also cooperate with emergency rescue work, which has high practical value and research significance.