What are the parts of the printed circuit board according to the distribution of the conductive layer? What are the parts of the printed circuit board?
to be placed in easy to operate. Try not to be blocked by peripheral devices. Multi-pin chips, integrated circuits, connectors and other devices must be marked component direction, pin number. Pin count can not be marked one by one, you can use every 5 or 10 pins to do a mark method.
corresponding location need to be a green oil is not covered with bare copper, easy to heat the components and production welding fixed. Shell is a metal exposed devices such as crystal, serial socket, USB seat, etc., it is best to connect the shell and ground to make it a better shield. Do not have holes or traces below the bare metal, as if it were unavoidable to lay a flat area of ??white oil in its corresponding position to avoid short circuits with other networks below it. Such as the circuit board need to operate the function keys such as settings, reset keys
Inductor and inductance as much as possible between the distance to avoid interference. The ground line as thick as possible, usually ≥ 50mil.8 circuit board components around the chip to be together, the ground to a little grounding, such as a large area of ??copper to be placed in the hole 9. Note that the components Package, especially the capacity of electrolytic capacitors, relay polarity, frog-type switch pin positioning. Do double-sided panel to note that the smallest aperture of the hole is 0.5mm outer ring 0.8mm, the thinnest lines and line spacing of 8mil. The same circuit board in the hole type to be as little as possible. In the high-power devices directly board,
The number of traces of the aperture as little as possible .2. In a single panel can not be traced with unclean holes, traces can not have edges .3. Jumper type as little as possible. . Large area of ??the alignment, to be hatched into the block-based main line .5. Single-sided line spacing to be ≥ 20mil; double-panel line spacing to be ≥ 10mil, such as patch IC pin spacing is only 0.5mm, IC Some of the areas around the pin are adjustable to 8 mil. Power supply circuit, bypass capacitor as close as possible to the chip pin.
