It's a chip integrated circuit. It mainly includes SOP, SOJ, PLCC, LCCC, QFP, BGA, CSP, FC, MCM, etc. Such as: SOIC IC: Size specifications: SOIC08, 14, 16, 18, 20, 24, 28, 32 QFP close-pin integrated circuit PLCC integrated circuit: PLCC20, 28, 32, 44, 52, 68, 84 BGA ball grid array package integrated circuit: Array spacing specifications: 1.27, 1.00, 0.80 CSP integrated circuit: component side length does not exceed 1.2 times the side length of the chip inside, array spacing < 0.50 microBGA, etc. It uses SMT Technology [SMT is the abbreviation of Surface Mounted Technology], which is the most popular technology and process in the electronic assembly industry at present. One of the components used.