Microcurrent leakage image detection method and system

Abstract

The invention provides a microcurrent leakage image detection method and system, and the system comprises a power supply, a phase locking device, an image collection module, and an image processing module. The phase locking device is used for controlling the power supply to transmit a periodic square voltage with a preset first frequency f to a detected PCB, wherein an invalid device on the PCB generates periodic heat with the same frequency as the first frequency, and the a periodic square voltage with a preset second frequency F is transmitted to the image processing module synchronously (F>>2f). The image collection module is used for carrying out the infrared image collection of the detected PCB according to the periodic square voltage with the second frequency. The image processing module is used for processing the collected infrared image, so as to obtain a positioning image of the invalid device on the detected PCB. The system can solve a problem of detecting a microampere level electric leakage fault on the PCB, and achieves the fault locating and detecting of a micro-short-circuit device.

Description

technical field [0001] The invention relates to the technical field of leakage current detection, in particular to a micro-current leakage image detection method and system thereof. Background technique [0002] All objects in nature and substances above absolute zero can produce infrared rays (Infrared Radiation, IR), which modern physics calls heat rays. Infrared thermal imaging cameras are widely used in fault diagnosis in the electronics manufacturing industry, especially for the location of short-circuit faults, which have the characteristics of intuition, non-contact, fast diagnosis speed and high accuracy. Such as figure 1 as shown, figure 1 It is a schematic structural diagram of a micro-current leakage image detection system in the prior art. The power supply powers on the PCB board to be tested. After power-on, the infrared thermal imager takes images of temperature changes at various points on the surface of the PCB board to be tested, and then inputs them into ...

AI Technical Summary

Problems solved by technology

[0003] However, facing the increasing integration of printed circuit boards (PCB) and smaller devices, thermal imaging cameras have limited ability to locate faults with small currents and small heat generation, so infrared thermal imaging cameras are directly used Unable to locate mobile phone leakage current, micro-short circuit and other faults

Existing thermal imaging cameras have low test accuracy, and can only locate faults with a leakage current of more than 2mA, and cannot locate leakage currents below 2mA, especially at the microampere level; Locating micro-short circuit faults

[0004] Therefore, it is urgent to find a micro-ampere-level fault detection device that can solve the problem of fault location for micro-short circuits in PCB boards.

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