What are the requirements of PCB manufacturing process for pads?
The pad is the basic unit of PCB surface mount assembly. As an excellent PCB engineer, it is essential to have a wealth of knowledge reserves of pads. So, do you know what the PCB manufacturing process requires for pads? Let's take a closer look: 1. Test points should be added to the pads that are not connected to the plug-in components at both ends of the chip components. The diameter of the test points is equal to or greater than 1.8mm to facilitate online tester testing. 2. For IC pin pads with dense pin spacing, if they are not connected to the hand plug-in pads, test pads need to be added. The diameter of the test point is equal to or greater than 1.8mm to facilitate online tester testing. 3. If the distance between the pads is less than 0.4mm, white oil must be applied to reduce continuous soldering when the wave crest is exceeded. 4. The two ends and ends of the SMD component should be designed with lead-tin. The lead-tin width is recommended to use 0.5mm wire, and the length is generally 2 or 3mm. 5. If there are hand-soldering components on the single panel, remove the tin bath in the opposite direction to the tin passing direction, and the width of the hole is 1.0mm to 0.3mm. 6. The spacing and size of the conductive rubber keys should be consistent with the actual conductive rubber keys. The PCB board connected to this should be designed as a gold finger, and the corresponding gold plating thickness should be specified. 7. The size and pitch of the pad should be exactly the same as the size of the patch component. The above are the requirements of PCB manufacturing process for pads. How much do you know?