PCB News - The advantages and disadvantages of soft and hard board

There are many advantages of using Rigid-flexBoard, which are listed as follows:

The signal transmission distance is shortened and the speed is increased, which can effectively improve the reliability
The traditional signal transmission through the connector is [circuit board-connector-soft board-connector-circuit board], while the signal transmission of the soft and hard board is reduced to circuit board-soft board-circuit Board, the signal transmission distance is shortened, and the problem of signal transmission attenuation between different media is also reduced. Generally, the circuit on the circuit board is made of copper, while the contact terminals of the connector are gold-plated, and the solder pins are It is fully tin plated and needs to be soldered on the circuit board with solder paste. The signal transmission between different media will inevitably be attenuated. If you switch to a flexible and hard board, these media will become less and the signal transmission ability will also be reduced. It can be relatively improved, and the reliability of some products with higher signal accuracy requirements will help improve their reliability.

It can effectively save the space on the circuit board and save the process of using connectors or HotBar
Because the rigid and flexible boards are already combined, the space that originally required the use of connectors or the HotBar process can be saved. For some flexible and rigid boards with high-density requirements, one less connector is needed. Space is like picking up a treasure. In this way, it also saves the cost of parts using the connector or the cost of the HotBar process. In addition, the space between the two rigid-flex board boards can be made tighter by eliminating the need for connectors.

Simplify product assembly and save assembly man-hours
The use of soft and hard board can reduce the man-hours of SMT parts, because the number of connectors is reduced. It also reduces the man-hours for assembly of the whole machine, because it eliminates the assembly action of inserting the soft board into the connector, or eliminates the HotBar manufacturing process. It also reduces the cost of parts management and inventory, because the BOM is reduced, so the management becomes less.

The shortcomings of the soft and hard board
After the introduction of the supplier, it is generally understood that if you simply compare the [soft and hard board] with [soft board+ circuit board + connector], the biggest disadvantage is [soft and hard] The price of the combined board is more expensive, and it may be more than the original price of the simple [soft board + hard board], but if you deduct the price of the connector or the cost of the HotBar, the price will be

It is possible that they will tend to be consistent, and the detailed costs may have to be actuarially calculated to have a clearer outline. Another disadvantage is that SMT parts and furnaces may need to use a carrier to support the part of the soft board, which virtually increases the assembly cost of SMT.