What are the PCB layout design inspection elements?
1. The preferred route has been determined and all devices have been placed on the board.
2. The origin of the coordinate is the intersection of the lower left extension of the board frame, or the lower left pad of the lower left socket.
3. The actual PCB size, positioning device position, etc. are consistent with the process structure element diagram, and the equipment layout is in the area where the equipment height is required to meet the structural element map requirements.
4. The DIP switch, reset device, indicator light, etc. are in the correct position, and the handlebar does not interfere with the surrounding equipment.
5. The outer frame of the panel is 197 mils smooth or designed according to the structural dimensions.
6. The conventional board has a process edge of 200 mils; the machined edges on the left and right sides of the backsheet are greater than 400 mils, and the machined edges on the upper and lower sides are greater than 680 mils. Place the device in a location that does not conflict with the open position of the window.
7. All additional holes (ICT locating holes 125 mil, handlebar holes, elliptical holes and fiber clip holes) need to be added and set up correctly.
8. Wave soldering process wave spacing, device orientation, device spacing, device library, etc. take into account the requirements of wave soldering.
9. Device layout spacing meets assembly requirements: surface mount devices greater than 20 mils, ICs greater than 80 mils, and BGAs greater than 200 mils.
The crimp member is greater than 120 mils in the surface area of the component that is higher than its components, and there is no device in the penetration region of the weld surface crimp member.
11. There are no short-circuit devices between the high-end devices. There are no chip devices and short insertion devices between the devices with a height greater than 10 mm placed within 5 mm.
12. Polar equipment has a polar screen printed logo. The same type of polar insertion components X and Y are identical in their respective directions.
13. All equipment has been clearly identified, and P*, REF, etc. are not clearly identified.
The surface containing the chip device has 3 positioning cursors and is in an "L" shape. Position the center of the cursor at a position 240 mils or more from the edge of the board.
15. If slab processing is required, the layout is easy to imposition, which facilitates PCB processing and assembly.
16. The notched plate edge (formed edge) should be filled by the slot and stamp hole. The stamp holes are non-metallic and are typically 40 mils in diameter and 16 mil apart.
17. The debug test points have been added to the schematic and the position in the layout is appropriate.