Nowadays PCB design time is getting shorter
Therefore, the relationship between the hole and the pin inductive reactance must be considered and the priority of the pass hole specification must be set.
Therefore, the relationship between the hole and the pin inductive reactance must be considered and the priority of the pass hole specification must be set.
The size of the digital circuit output current Ioh pulled from the power supply at high voltages and the current Iol injected at low voltages is generally different, that is, Iol > Ioh.
As a result, future digital life situations such as remote teaching, intelligent diagnosis and treatment, and AI for industrial risk control have been started in advance.
Increase the dielectric constant of PCB board, which can prevent the high frequency parts such as the transmission line near the board from radiating outward.
In PCB, there are only two kinds of transmission lines: strip line and microwave line. The biggest problem of transmission line is reflection, which will cause many problems.
According to Prismark statistics, mobile terminal PCB demand is mainly HDI and flexible board (HDI board accounts for about 50.68%), and has 26.36% packaging substrate demand.
PCB circuit opening and short circuit are the problems encountered by PCB manufacturers almost every day, which has been troubling the production and quality management personnel.
In a high speed PCB, wiring is more than just connecting two points. As a qualified engineer, wiring is a hybrid knowledge carrier including resistance, capacitance and inductance.
Starting from the most basic PCB board, this paper discusses the function and design skills of PCB stacking in controlling EMI radiation.
All of these problems can cause the solder shield to detach from the circuit board and eventually lead to corrosion of the copper circuit.
In terms of PCB design, 50 ohm is also selected after comprehensive consideration. In terms of PCB wiring performance, generally low impedance is better.
When PCB is used for hot air leveling and component welding, the board is subjected to high temperature (> 200), will also release trace amounts of hydrogen bromide。