When manufacturing a PCB, precise calculation of PCB trace width is very crucial. Incorrect PCB tracing will lead to a poor PCB design, resulting in faulty PCB. In this article, you’ll get all the details regarding PCB trace width calculator and some more calculators you should know about if you’re working on an electronics project.
What’s a PCB trace width calculator?
Copper plates that connect all the components on a PCBA are called traces. These traces act like an electric conduction, and have a specific width, that resemble wires in an electric circuit. The PCB manufacturers cannot keep the width of the trace according to their wishes.
IPC-2221 mentions certain formulas and calculations to calculate the appropriate width of the trace. Trace width calculation is very complex, which is why there are several online trace width calculators available on the internet. These trace width calculators will ask for a few parameters and will give you the correct trace width needed for your PCB.
Trace width is calculated at the beginning of the PCB manufacturing, during the PCB design process. The width calculation allows manufacturers to understand the correct size of the entire PCB, placement of different components, calculate space for drilling holes, etc.
Why is a PCB trace width calculator important?
There are several reasons that make a PCB trace width calculator important. These include:
●Incorrect trace calculation can cost a loss of thousands or millions of dollars to the manufacturers. The PCB manufacturers can avoid this loss by using trace width calculators, that generate error-free results.
●Trace width calculators are easy to use if you have all the input parameters. They generate results quickly, which help PCB manufacturers save a lot of time in the designing process.
●Not only do trace width calculators calculate the trace width, many calculators explain their calculation, so the manufacturers can cross check that the calculator is giving the required value.
PCB trace width calculator: External Vs. Internal
Traces can be internal and external. The external traces are what you can see on the outermost layers of a PCB. These traces are visible by naked eyes. If talking about multi layer PCB, there can be internal traces, that are sandwiched between the layers of PCB. These are not visible, but have a specific width.
A calculator that calculates external traces’ width is called “external trace width calculator”, and the one calculating internal traces’ width is called “internal trace width calculator”.
●Assuming that the maximum current, trace thickness, and maximum temperature rise are same while calculating the internal and external trace width, the required trace width will be higher for internal trace than external trace. Similarly, the cross section value will be higher in internal trace width than external trace width.
Ideal width of PCB traces
While the width of a PCB trace depends upon several inputs, there’s still an ideal value for PCB trade width. Experts suggest that the ideal PCB trace width is 35µm, which is also equivalent to 1 ounce per square feet. On the other hand, minimum trace width is expected to be 0.152mm.
How to calculate PCB trace width?
To calculate trace width, you need to have a few input parameters:
●Maximum current (I)
●Trace thickness (T)
●Maximum desired Temperature
1.Calculate the area
A = (I / (k * TRISEb))1/c
2.Calculate trace width
W = A / (T * 1.378 [mils/oz/ft2])
How to use PCB trace width calculator?
If the manual method sounds complex, you can easily take the easier road by using a PCB trace width calculator.
To use a calculator, please search for any PCB trace width calculator. It’ll ask for a few inputs- desired maximum temperature, maximum current, and trace thickness. Enter the values and click the generate/calculate button.
Some calculators have an advanced mode, which asks for additional inputs- ambient temperature and length. Based on these inputs, it’ll generate additional outputs- trace temperature, resistance, voltage drop, and power dissipation.
Things to know before calculating PCB trace width
A few things you should know before beginning with the trace width calculation:
●Maximum current that’ll flow through the trace
●Trace thickness, as it’ll impact the overall conduction
●Maximum temperature rise, that’ll impact the need for heat conduction later on
●Ambient temperature, assuming that your PCB will be used in extremely hot environments or cold environments
●The length of the trace
Before beginning with the trace calculation, ensure that you have the following prerequisites:
1.You know how many layers your PCB will have.
2.You should have an exact idea what gadget’s PCB you’re making for.
3.You must be aware that your PCB might be used in different parts of the world, so ambient temperature must be considered strictly.
4.Make sure that you have a well-defined list of all the components that’ll be placed on your PCBA.
More calculators for your electronics projects
Apart from PCB trace width calculator, you should also have an idea of these calculators if you’re into PCBs and electronics projects. These calculators can help you get the right values needed for your projects.
1.PCB Trace Maximum Current Calculator
Similar to trace width calculator, this tool in particular will help you calculate the maximum current your internal and external trace should have. For this, you should know the these values- trace width, trace thickness, and maximum desired temperature.
2.Schematics Converter
This is a tool that you can use to convert your electrical schematics into any desired and supported formats.
3.Trace Resistance Calculator
You can calculate resistance in your trace by giving input values- trace width, length, trace thickness, and ambient temperature.
4.Resistor Calculator
If you’re looking to decode the resistor codes, this particular tool can help you decode and calculate the resistor for a 4 band, 5 band, and 6 band resistor.
Conclusion
After learning about trace widths and how to use a trace width calculator, you might have observed that trace width is a complex and critical thing, which can affect an entire PCB project. If you’re up for an electronics project, it’s highly recommended reaching out to a professional such as IBE Electronics, who’ll take care of trace width calculation and will avoid and errors. Since IBE Electronics is a professional and expert in the electronics industry, there’s no chance of anything going wrong in trace width calculation.
- The temperature rise of the trace
- The resistance value of the trace
- The voltage drop across the trace
- Dissipated power along the trace
●Maximum current that’ll flow through the trace
●Trace thickness, as it’ll impact the overall conduction
●Maximum temperature rise, that’ll impact the need for heat conduction later on
●Ambient temperature, assuming that your PCB will be used in extremely hot environments or cold environments
●The length of the trace
To calculate trace width, you need to have a few input parameters:
●Maximum current (I)
●Trace thickness (T)
●Maximum desired Temperature
1.Calculate the area
A = (I / (k * TRISEb))1/c
2.Calculate trace width
W = A / (T * 1.378 [mils/oz/ft2])
