IEC 60384-21:2019

Overview

IEC 60384-21:2019 is the sectional specification for fixed unencapsulated surface mount multilayer capacitors (MLCCs) of ceramic dielectric, Class 1, intended for use in electronic equipment. It applies to capacitors with metallized connecting pads or soldering strips designed for mounting on printed circuit boards (PCBs) or directly on substrates for hybrid circuits. The standard prescribes preferred ratings and characteristics, selects appropriate quality assessment procedures and test/measurement methods from IEC 60384-1, and defines general performance requirements. Capacitors specifically intended for electromagnetic interference (EMI) suppression are excluded (see IEC 60384-14).

Key Topics and Requirements

• Preferred ratings and characteristics: rated temperature, rated voltage, category voltage, nominal capacitance ranges and tolerances, temperature coefficient and dimensions (including newly added 0201M size).
• Quality assessment procedures: primary manufacture controls, qualification approval, fixed sample size plans, and quality conformance inspection rules. Test severities in detail specifications must be equal to or higher than those in this sectional specification; lower levels are not permitted.
• Test and measurement methods: visual inspection, dimensional checks, capacitance and loss-angle (tan δ) measurement, insulation resistance, voltage proof, temperature coefficient and temperature cycle drift, shear tests, substrate bending, resistance to soldering heat, solderability, rapid temperature change, climatic sequence, damp heat (steady state), endurance and related recovery procedures.
• Mounting and marking: requirements for mounting on PCBs/hybrid substrates, marking on the body and packaging, and information to be provided in a detail specification (outline drawing, soldering recommendations).
• Structure and harmonization: updated to align with ISO/IEC Directives, Part 2:2016 and harmonized with IEC 60384-22.

Applications and Who Uses It

• Applicable for component manufacturers and designers specifying surface mount multilayer ceramic capacitors (SMT MLCCs) with Class 1 dielectric.
• Used by quality assurance and reliability engineers, procurement teams, test laboratories, and PCB/hybrid circuit designers who require defined performance, testing, and acceptance criteria.
• Typical application contexts include electronic equipment where stable capacitance over temperature and reliable SMD mounting are required.

Related Standards

• IEC 60384-1 - General rules for fixed capacitors (referenced for tests and assessment procedures).
• IEC 60384-14 - Fixed capacitors for EMI suppression (exclusion scope).
• IEC 60384-22 - Harmonized sectional specifications for related capacitor types.

Keywords: IEC 60384-21, surface mount multilayer capacitors, ceramic dielectric Class 1, MLCC, SMT capacitors, quality assessment, solderability, endurance testing, capacitor specifications.