In the design of veterinary B-ultrasound boards, wiring is the key step to complete the design, and most of the previous work is prepared for it. In the entire board design, the wiring design process has the most restrictions, the most delicate skills, and the largest workload. The wiring should follow the following basic principles:

(1) In the wiring design of the veterinary B-ultrasound motherboard, the printed wires should be as short as possible, especially in high-frequency circuits; the address lines or data lines of the same component should be kept as long as possible; the corners should be 45 degrees or rounded; when double-sided wiring, the wires on both sides should be perpendicular, oblique or curved to avoid parallelism and reduce parasitic coupling; the printed wires used for circuit input and output should be avoided as much as possible. Parallel, it is best to add a ground wire between these wires.

(2) In the wiring design of the veterinary B-ultrasound motherboard, the wire width should meet the electrical performance requirements and be easy to produce. The minimum width is mainly determined by the adhesion strength between the wire and the insulating substrate and the current value passing through. The minimum should not be less than 0.2mm. In high-precision, high-density printed circuits, the wire width and spacing can generally be 0.3mm.

(3) In the wiring design of the veterinary B-ultrasound motherboard, no cross circuits are allowed in the printed circuit board. For possible cross lines, drilling and winding methods can be used to solve the problem, that is, let the lead wires drill through the gaps under other resistors, capacitors, and transistors.

(4) In the wiring design of the veterinary B-ultrasound motherboard, the common ground wire of the printed conductor should be arranged at the edge of the printed circuit board as much as possible, and as much copper foil as possible should be retained on the printed circuit board as the ground wire; the common ground wire is best to form a loop or a mesh, so as to ensure that the ground potential difference is reduced; a multi-layer printed circuit board can use several layers as shielding layers, and the power layer and the ground layer can be regarded as shielding layers. Generally, the power supply and ground layer are on the inner layer of the multi-layer printed circuit board, and the signal line is designed on the outer or inner layer.

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