SMT chip processing has certain requirements for pads, and a better pad design can lay a firmer and more efficient foundation for subsequent PCBA circuit board manufacturing. Today the professional technicians of Jedduobang will introduce to you what are the requirements of the pads in china pcb SMT chip processing, let's take a look.

1. For SMT components on the wave soldering surface, the pads of larger components (such as transistors, sockets, etc.) should be appropriately increased. For example, the pad of SOT23 can be lengthened by 0.8-1mm to avoid the "shadow effect" of the component causing empty soldering.

2. The size of the pad should be determined according to the size of the components. The width of the pad is equal to or slightly larger than the width of the welding rod of the component, and the welding effect is the best.

3. Generally, between two interconnected components, we will avoid using a single large pad. This is because the solder on the large pad will connect the two components to the middle. The correct method usually adopted is to separate the pads of the two components and connect them with a thinner wire between the two pads. If the wires are required to pass a larger current, several wires can be connected in parallel, and the wires are covered with green oil.

4. There should be no through holes on or near the pads of SMT components. Otherwise, during the REFLOW process, the solder on the pads will flow away along the through holes after melting, resulting in virtual soldering, less tin, or flow Causes a short circuit to the other side of the board.

The above four points are the requirements for pads in SMT multilayer PCB patch processing. I hope this article can help you~