PCB board selection of lead-free spray tin and lead spray tin difference: 1, lead-free spray tin belongs to environmental protection process, does not contain harmful substances "lead", the melting point is about 218 degrees; 2, lead spray tin d...
In order to ensure the smooth completion of the special process and facilitate the PCBA welding process, PCB board must meet the manufacturability requirements in dimensions, pad distance and other aspects
The temperature of PCB board is related to the temperature of its raw materials, solder paste and surface parts. Usually, the highest temperature resistance of PCB board is 300 degrees, 5-10 seconds; Over lead-free wave soldering temperature is about 260,
PCBA processing using expired PCB board three hazards: 1, PCBA processing using expired PCB may cause oxidation of PCB surface welding pad, 2, PCBA processing using expired PCB may cause moisture absorption and burst board, 3, PCBA processing using expire
The importance of PCBA processing plant to select the SMT placing machine is as follows: first, the type of components that can be affixed, second, the adjustment of the placing machine
In short, the technological parameters and conditions of copper plating must be strictly controlled to ensure that the thickness of the copper plating layer in the hole meets the requirements of the technical standard.
It is said that PCB manufacturers marketing girl is a arrived at five gourd baby, specializing in the treatment of customers with various difficult and complex diseases, professional mediation factory is not satisfied。
Impedance is usually denoted by z, z is a complex number, the real part is called resistance, the imaginary part is called reactance, and the unit of impedance is ohm.
New design PCB board to find the fault method: 1. Voltage measurement method, 2. Signal injection method, 3. See, hear, smell, touch
Board explosion caused by water absorption accounted for 70% of the defects, other reasons such as PCB structure uneven growth and contraction, cold and heat imbalance, process injury and bad blackening.
As an electronic engineer design circuit is a necessary hard work, if the PCB design is not reasonable performance will be greatly compromised.
Harm of PCB board deformation: on the automatic surface mounting line, if the circuit board is not smooth, it will lead to inaccurate positioning, components can not be inserted or installed in the hole of the board and surface mounting pad, and even dama