I am now at the stage of choosing caps and resistors for this circuit I am looking at the method of selection at http://www.mouser.com/Passive-Components/Capacitors/Ceramic-Capacitors/_/N-5g8m/ as given to me by #12 of this forum, but am confused as to whether the case code is imperial or metric. How do I tell please. I am leaning towards imperial because it lists both the 0603 and 0805 which are the only two case codes used in my circuit, whereas the metric listing here http://www.resistorguide.com/resistor-sizes-and-packages/ only list 0603 in the metric codes if that makes sense. Any help appreciated please.

 

These are imperial size codes commonly used in the USA. The 0805 and 0603 are sizes people start with in the design.

The best way to differentiate the two is to look at the datasheet and check to physical size if the part. This usually appears near the end of the datasheet. There willbe a drawing that shows all of the dimension and tolerances.

 

Just looked at the mouser link that you posted, on my android phone. They give you opportunity to search for parts in both inches, imperial, and millimeters, metric. There is a Case Code - in and Case Code - mm in the search options.

 

Just looked at the mouser link that you posted, on my android phone. They give you opportunity to search for parts in both inches, imperial, and millimeters, metric. There is a Case Code - in and Case Code - mm in the search options.

StayatHomeElectronics - thanks for your reply but I don't think that I explained myself very well. I am trying to replicate a PCB for which the circuit schematic has been released under Creative Commons. All I have available to me is a sample production board and the Eagle schematic with associated library information. From the library package information I have these sizes for the nineteen capacitors and resistors used in the circuit and I am trying to identify whether they are metric or imperial case sizes that have been used so that when I get the board made the parts on the BOM will match the pad sizes on the PCB. Here is a list of the capacitors and resistors used. Thanks for any help as I am lost here

C1 1uf 0603
C2 1uf 0603
C3 1uf 0603
C4 0.1uf 0603
C5 0.01uf 0603
C6 0.1uf 0603
C7 0.1uf 0603
C8 2.2nf 0603
C9 10uf 0603
C10 10uf 0805

R1, R4, R5, R6, R7, R8, R9 - 10KΩ 0603
R2, R3 - 22Ω 0603

 

Most boards in the USA will reference imperial sizes. That would also be my guess from looking at the picture you provided.

If you are still unsure, you can check the sizes by verifying the sizes of the parts and comparing them to the information provided in a part datasheet.