Chip Resistor: Chip Non-polarized Capacitor: Chip Inductor: Chip Diode: Chip LED: Chip Antenna: Chip Polarized Capacitor:
Here is a table listing the Chip package Case Code and package dimensions for "Standard Chips"
If the Chip dimensions do not match the table then a new or different Case Code must be assigned.
Note: there are various Heights to all of these packages, but the Height does not impact the resulting pad size for the Footprint Land Pattern.
However, the Height is important for the 3D STEP model creation and should be included in the Footprint name.
Also, the Terminal Lead may be a different length and that should be included in the Footprint Name because that does affect the resulting pad size.
Here is a typical Footprint Name for a 0201 (0603 Metric) Capacitor part:
Footprint Land Pattern Name: CAPC60X32X27L15
CAP = Capacitor C = Chip 60 = 0.60 mm body Length 32 = 0.325 mm body Width 27 = 0.275 mm maximum Height L15 = 0.15 mm nominal Lead Length
Notice that the Leading Zeros are ignored and only the first 2 numbers to the right of the decimal point is used in the Footprint Name.
But the Leading zeros are in the Case Code. The Case Code = one number to the left and right of the decimal point.
A typical Physical Description for this package will be: Capacitor, Chip; 0.60 mm L X 0.325 mm W X 0.275 mm H body
The EIA Inch Based Names are still widely used today in the electronics industry, even though the Metric Names created by EIAJ in Japan were first introduced in the 1980's in the PDP-100 publication. American assembly shops, EE engineers and component manufacturer's did not adapt to the metric naming convention and translated all of the original documentation from Metric to Imperial units so they could better comprehend the package sizes. This was one of the biggest mistakes in the global electronics industry and very short sited of the future of the industry.
Today, all Standard package dimensions are printed using Metric Dimensions but the translated Inch Based package names have deep roots in the industry and have settled as the defacto standard. Now we have to deal with 2 systems of measurement rather than the supreme metric unit measuring system.
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