1. What is thermal pad
The so-called thermal pads, refers to the bottom of the components with the metal side of the heat dissipation solder pads, usually relatively small power, mainly through the heat dissipation pads on the heat dissipation holes to the ground layer. In order to better heat dissipation, sometimes need to design the heat sink hole for through-hole (not plug hole), so that reflow soldering molten solder will flow to the back, the formation of tin beads, thus affecting the solder paste printing on the surface of the beads.
2. Design requirements
(1) In order to reduce the phenomenon of tin beads, the hole can be designed for a diameter of ≤ 0.30mm or ≥ 0.80mm hole; resin plug hole surface plating (POFV) design can also be used.
(2) Lay out all the heat sink pads on the secondary soldering surface to accept the presence of tin beads.
(3) Design the thermal process layer. If the PCB board thickness < 2.4mm, and the number of ground layers connected to the heat sink hole < four layers, the general molten solder will flow into the heat sink hole and the formation of tin beads phenomenon. Therefore, it is recommended that if the number of ground layers connected with the heat sink < four layers, you can design the heat sink process layer (of course, the number of PCB layers must be able to achieve), as long as the heat sink is connected to the large copper surface more than six layers, generally will not form the tin bead phenomenon.
Features of NeoDen IN12C reflow oven
1. Built-in welding fume filtration system, effective filtration of harmful gases, beautiful appearance and environmental protection, more in line with the use of high-end environment.
2. The control system has the characteristics of high integration, timely response, low failure rate, easy maintenance, etc.
3. Unique heating module design, with high precision temperature control, uniform temperature distribution in the thermal compensation area, high efficiency of thermal compensation, low power consumption and other characteristics.
4. beautiful and has a red, yellow and green alarm function of the indicator design.
5. Custom-developed track drive motor according to the characteristics of the B-type mesh belt, to ensure uniform speed and long life.
Post time: Nov-15-2022