The design of trace width, spacing, and vias needs to be adjusted according to the specific PCB design requirements. Trace width calculator, here are some general recommendations for designing trace width, spacing, and vias:
1. Under normal conditions, the trace width/spacing should be controlled to 6/6 mils, with via size selected as 12 mils. For PCBs that meet this requirement, more than 80% of PCB manufacturers can produce them at the lowest cost.
2. The minimum trace width/spacing can be controlled to 4/4 mils, with a via size of 8 mils. For PCBs that meet this requirement, more than 70% of PCB manufacturers can produce them, although the price is slightly higher than the first option.
3. The minimum trace width/spacing can be controlled to 3.5/3.5 mils, with a via size of 8 mils. For this design specification, a significant number of manufacturers may not be able to produce it.
4. The minimum trace width/spacing can be controlled to 2/2 mils, with a via size of 4 mils. This generally involves HDI blind and buried vias, requiring laser vias. Most PCB manufacturers cannot produce these trace widths and spacings, and the cost is the highest.
The trace width/spacing rules mentioned above refer to the dimensions between elements such as trace to hole, trace to trace, trace to pad, trace to via, and hole to pad.
The design of BGA (Ball Grid Array) trace width/spacing can refer to:
1. Setting rules should consider the design bottlenecks in the design files. For instance, if there is a 1mm BGA chip with shallow pin depth, and there is only one signal line needed between two rows of pins, it can be set to 6/6 mils.
2. If the pin depth is deep, and two signal lines are needed between two rows of pins, it should be set to 4/4 mils; for a 0.65mm BGA chip, it is generally set to 4/4 mils.
3. For a 0.5mm BGA chip, the minimum trace width/spacing must generally be set to 3.5/3.5 mils; for a 0.4mm BGA chip, HDI design is usually required. For design bottlenecks, area rules can be set with smaller local trace width/spacing and larger rules set for other areas of the PCB to facilitate production and improve PCB yield.
At a certain frequency, the resistance encountered by high-frequency signals or electromagnetic waves propagating through the signal traces relative to a reference layer is referred to as characteristic impedance. When manufacturing PCBs, whether to control impedance is determined based on customer requirements. If the customer requests that a specific trace width requires impedance control, the impedance of that trace width must be managed during production. When signals are transmitted on a PCB, the characteristic impedance of the PCB must match the electronic impedance of the components at both ends. If the impedance values exceed the tolerance, reflected, scattered, attenuated, or delayed signals can occur, leading to incomplete signals or signal distortion. Trace width calculator
There are three main types of commonly used software impedance models:
(1) characteristic impedance, also known as single-ended impedance;
(2) differential impedance;
(3) coplanar impedance, also known as coplanar waveguide impedance, which is primarily used in double-sided impedance design. Trace width calculator