Abstract: A substrate is placed in a reflow oven, where a solder flux volatilized in the reflow oven is capable of adhering to a surface of the substrate to form a solder flux layer, a thickness of the solder flux layer is detected, and a concentration of the solder flux in the reflow oven is calculated based on the thickness of the solder flux layer.

Abstract: This application provides a circuit board assembly and an electronic device. The circuit board assembly includes a circuit board, a chip, a shielding cover, and a conductive structure. The circuit board includes a first surface and a second surface that are disposed opposite to each other. The chip is disposed on the first surface. The shielding cover defines accommodation space, a recess is provided on a surface of the shielding cover facing the first surface, and the recess runs through the shielding cover and is communicated with the accommodation space. The conductive structure is located in the recess and connected between a top wall of the recess and the first surface, and orthographic projection of the conductive structure on the circuit board at least partially falls within an orthographic projection range of the chip on the circuit board.

Abstract: A substrate is placed in a reflow oven, where a solder flux volatilized in the reflow oven is capable of adhering to a surface of the substrate to form a solder flux layer, a thickness of the solder flux layer is detected, and a concentration of the solder flux in the reflow oven is calculated based on the thickness of the solder flux layer.