In the microphone industry, in the pcb board of mems sensors (micro electro mechanical systems), one end of the capacitor is usually connected to a large piece of copper foil 4 'through the first bonding pad 1'
and the other end is connected to the circuit 3 'through the second bonding pad 2'. In traditional technology, the first pad 1 'and the second pad 2' are usually formed directly on the corresponding large piece of copper foil 4 'and line 3' during welding. During soft melt welding, the pad pin heats up and the solder paste melts.
The first pad 1 'at one end of the large piece of copper foil has a slow heat transfer speed due to the large area of the copper foil,
and the welding temperature rises slowly, while the second pad 2' at the other end of the line 3 'heats up quickly due to the small area of the line 3',
resulting in uneven stress on both ends of the capacitor, It is easy to build a monument, which seriously affects the welding efficiency and welding cost of capacitors.
A pcb board for mems sensors, including: base copper foil, lines and electronic components. The base copper foil is provided with a first pad pin, and the circuit is provided with a second pad pin.
The difference between the area of the first pad pin and the area of the second pad pin is not more than 20%.
The electronic components are respectively connected with the corresponding base copper foil and the circuit through the first pad pin and the second pad pin.