The general thickness of the finished PCB circuit board is between 0.8mm and 1.6.mm, and the more common thickness specifications are designed by default in metric units of 1.6 mm (imperial units are about 63 mils). The standard of the plug-in is also adapted to the specification of 1.6mm. How did the thickness standard of 1.6mm come from? Today, the editor of the circuit board manufacturer will take you to understand the origin of this standard

　　In the electronic tube era, the PCB industry was still in its infancy. Due to the large heat generation and bulkiness of the electronic tube components, it was inconvenient to install on the printed circuit board (a certain degree of mechanical strength was required). At that time, the production of electronic products was basically manual construction. Shed installation, of course, is also related to the development of PCB substrate materials. Manufacturing technologies such as epoxy resin as PCB substrate, reinforcement material for PCB substrate, and copper foil have not yet been commercialized.

　　Phenolic laminate is a sturdy and well-insulated polymer material with heat resistance, water resistance, chemical resistance and high current capability. Although it was not developed specifically for circuit board use, it is more widely used in decoration However, the strength of phenolic laminate is much better than that of gypsum board, cardboard, or veneer, whether it is drilling performance or used as a mounting support for electronic tubes, so PCB manufacturers choose phenolic laminate instead of cardboard or thin Wooden boards come naturally as circuit boards.

　　But punching holes in the phenolic laminate and wiring all the electronic components together is still a lot of work, even harder than playing with perfboard, which has holes pre-drilled. It didn't take long for someone to figure out a way to stick a piece of copper foil on a phenolic laminate, and then etch the interconnects between the components on the copper foil (in 1913, Berry in the United Kingdom invented the use of anti-corrosion agent is coated on the metal foil, and then the uncoated part is etched to form a conductive pattern), which makes a single-sided printed circuit board. Soon, the development of interconnection systems between multiple circuit boards created a related need for board-to-board connectors.

　　And 1/16 inch or 63 mil is the production thickness of phenolic laminate at that time, and the board-to-board connector is naturally designed according to the board thickness of 1/16 inch (about 63 mil or 1.6 mm), which forms a matching In the industry chain, the 1/16-inch (about 63mil or 1.6mm) plate thickness has also formed the industry default standard.

　　Nowadays, the development of substrate materials has been very diverse, but 1.6mm (or 63mil in imperial units) is still the default finished board thickness of PCB board manufacturers, but the standard board thickness range has been extended to 0.8mm~1.6mm. (The specific process is subject to the board factory, some board factories are 0.6mm~2.5mm)

Read recommendations:

High frequency PCB

Six-layer Immersion Gold Board (BGA)

DIP plugin

Six-layer Immersion Gold Board (BGA)

What are the responsibilities of the pcba Visual inspection position