Separator Options for the Designator Suffix
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Each part in a multi-part schematic component is uniquely identified by an alpha or numeric suffix. Altium Designer 13.2 extends the numeric suffix support by adding the choice of a dot or a colon as the suffix separator.
For the Multi-part component suffix, choose between Alpha, colonNumeric, or dotNumericThe Alpha Numeric Suffix type and separator is selected in the Schematic - General page of the Preferences dialog.