Ceramic Capacitor - Additional Information - Marking - Imprinted Markings

Imprinted Markings

Ceramic capacitors, like most other electronic components and if space enough exists, have imprinted markings to indicate the manufacturer, the type, their electrical and thermal characteristics, and their date of manufacture. In the ideal case, if they are large enough, the capacitor will be marked with:

• manufacturer's name or trademark;
• manufacturer's type designation;
• rated capacitance;
• tolerance on rated capacitance
• rated voltage and nature of supply (AC or DC)
• climatic category or rated temperature;
• year and month (or week) of manufacture;
• certification marks of safety standards (for safety EMI/RFI suppression capacitors)

Smaller capacitors use a shorthand notation, to display all the relevant information in the limited space. The most commonly used format is: XYZ J/K/M VOLTS V, where XYZ represents the capacitance (calculated as XY × 10Z pF), the letters J, K or M indicate the tolerance (±5%, ±10% and ±20% respectively) and VOLTS V represents the working voltage.

Examples:

• A capacitor with the following text on its body: 105K 330V has a capacitance of 10 × 105 pF = 1 µF (K = ±10%) with a working voltage of 330 V.
• A capacitor with the following text: 473M 100V has a capacitance of 47 × 103 pF = 47 nF (M = ±20%) with a working voltage of 100 V.

Capacitance, tolerance, and date of manufacture also can be identified with short code according to IEC/EN 60062. Examples of short-marking of the rated capacitance (microfarads):

• µ47 = 0.47 µF, 4µ7 = 4.7 µF, 47µ = 47 µF

The date of manufacture is often printed in accordance with international standards in abbreviated form.

• Version 1: coding with year/week numeral code, "1208" is "2012, week number 8".

• Version 2: coding with year code/month code,

Year code: "R" = 2003, "S"= 2004, "T" = 2005, "U" = 2006, "V" = 2007, "W" = 2008, "X" = 2009, "A" = 2010, "B" = 2011, "C" = 2012, "D" = 2013 e.t.c.

Month code: "1" to "9" = Jan. to Sept., "O" = October, "N" = November, "D" = December

"X5" is then "2009, May"

For very small capacitors like MLCC chips no marking is possible anymore. Here only the traceability of the manufacturers can ensure the identification of a type.