layout component direction of Pcb design you need to master
1. The design should be carried out in a certain order, for example, from left to right and top to bottom.
2. The width of the wiring strip and the spacing of the lines should be moderate. The spacing between the two pads of the capacitor should be as close as possible to the spacing of the capacitor leads.
3. When designing the wiring diagram, keep the lines as few as possible, and try to make the lines simple and clear.
4. When designing the wiring diagram, pay attention to the order of the pins, and the spacing of the components should be reasonable.
5. Wiring direction:
From the welding surface, the arrangement orientation of the components is as close as possible to the schematic diagram, and the wiring direction is preferably consistent with the wiring direction of the circuit diagram. Since it is usually necessary to perform various parameters on the welding surface during the production process, it is convenient to do so. Inspection, commissioning and overhaul in production (Note: Refers to the requirements of circuit performance and machine installation and panel layout requirements).
6. Under the premise of ensuring the performance requirements of the circuit, the design should be reasonable in the design, and the external wiring should be used less, and the wire should be routed according to the requirements of the requirements. It is intuitive, easy to install, height and overhaul.
7. Arrange the components, the distribution should be reasonable and uniform, and strive for neat, beautiful, and rigorous process requirements.
8. In and out of the terminal layout direction
(1) The distance between the two lead ends of the related ones is not too large, and it is generally suitable for about 2 - 3/10 inches.
(2) The inlet and outlet ends should be concentrated on 1 to 2 sides as much as possible. Do not be too discrete.
9. Potentiometer: The principle of placing the IC holder
(1) Potentiometer: used to adjust the output voltage in the regulator, so the design potentiometer should be full clockwise when the output voltage rises, the counterclockwise regulator will decrease the output voltage; in the adjustable constant current charger The potentiometer is used to adjust the charging current fold size. When the potentiometer is designed to be clockwise in full, the current increases. Potentiometer placement should be full of the structure of the whole machine and the layout of the panel, so it should be placed on the edge of the board as far as possible, with the handle turned outward.
(2) IC holder: When designing the printed board diagram, in the case of using the IC holder, it is necessary to pay special attention to whether the orientation of the positioning slot on the IC holder is correct, and pay attention to whether the IC pins are correct, for example, the first foot can only Located in the lower right corner or upper left corner of the IC holder, and close to the positioning slot (from the welding surface).
10.PCB Layout resistor, diode placement direction:
The pcb design is divided into two types: flat and vertical:
(1) Flat release: When the number of circuit components is small, and the size of the circuit board is large, it is generally flat. If the resistance is less than 1/4W, the distance between the two pads is generally Take 4/10 inch, 1/2W resistor flat, the spacing between the two pads is generally 5/10 inches; when the diode is laid flat, 1N400X series rectifiers, generally take 3/10 inches; 1N540X series rectifiers, generally Take 4 - 5/10 inches.
(2) Vertical: When the number of circuit components is large, and the size of the circuit board is not large, it is generally used vertically in the pcb design, and the spacing between the two pads is generally 1 - 2/10 when placed vertically. inch.