Новости PCB - некоторые элементы проверки и внимание при проектировании панелей PCB

In PCB design.Некоторые из вопросов проверки и внимания при проектировании панель PCB

проектный контроль

приводимый ниже перечень охватывает все аспекты, имеющие отношение к проектному циклу, в частности: приложения должны быть добавлены и к другим элементам.

a General project

1) Has the circuit been analyzed? разделение схемы на основные ячейки для сглаживания сигналов?
2) Does the circuit allow short or isolated key leads?
3) Where must be shielded, is it effectively shielded?
4) Have you made full use of the basic grid graphics?
5) Is the size of the PCB the best size?
6) Do you use the selected wire width and spacing as much as possible?
7) Has the preferred pad size and hole size been used?
8) Are the photographic plates and sketches appropriate?
9) Is the use of jumper wires the least? пересекать ли провод через узлы и агрегаты?
l0) Are the letters visible after assembly? они правильные размер и модель?
11) In order to prevent blistering, is there a window on the large area of copper foil?
12) Are there tool positioning holes?

Physical characteristics
1) Are all pads and their positions suitable for final assembly?
2) Can the assembled PCB meet the shock and вибрация conditions?
3) What is the required spacing of standard components?
4) Are the components that are not firmly installed or the heavier parts fixed?
5) Is the heating element cooling and cooling properly? или изоляция от PCB и других термочувствительных элементов?
6) Are the voltage divider and other multi-lead components positioned correctly?
7) Is the arrangement and orientation of the components easy to check?
8) Have all possible interferences on the PCB and the entire PCB assembly been eliminated?
9) Is the size of the positioning hole correct?
10) Is the tolerance complete and reasonable?
11) Have you controlled and signed the physical properties of all coating layers?
12) Is the diameter ratio of the hole and the lead wire within the acceptable range?

Mechanical design factors

Although the PCB adopts mechanical methods to support the components, Он не может быть использован как структурный элемент всего оборудования. On the edge of the printing plate, По крайней мере раз в 5 дюймов, чтобы получить некоторую поддержку.
The factors that must be considered when selecting and designing PCB are as follows;
1) PCB structure-size and shape.
2) Types of mechanical accessories and plugs (seats) required.
3) The adaptability of the circuit to other circuits and environmental conditions.
4) Consider installing the PCB vertically or horizontally according to some factors, как высокая температура и пыль.
5) Some environmental factors that require special attention, теплоотдача, вентиляция, shock, vibration, and humidity. пыль, salt spray and radiation.
6) The degree of support.
7) Keep and fix.
8) Easy to take off.

Electrical characteristics
1) Have you analyzed the influence of wire resistance, индуктивность, and capacitance? особенно, have you analyzed the key voltage drop phase grounding?
2) Does the spacing and shape of the wire accessories meet the insulation requirements?
3) Has the insulation resistance value been controlled and specified in key areas?
4) Is the polarity fully recognized?
5) Is the influence of wire spacing on leakage resistance and voltage measured from a geometrical point of view?
6) Has the medium for changing the surface coating been identified?