IEC 62024-2:2020

Overview

IEC 62024-2:2020 - High frequency inductive components, Part 2 - defines standardized measuring methods for the rated direct current (DC) limits of small inductors used in DC-to-DC converters. The standard makes it possible to compare DC current ratings across manufacturers by specifying how to measure the two primary limiting mechanisms: DC saturation (inductance reduction under DC bias) and temperature-rise (self-heating under DC current). It applies to leaded and surface-mount inductors with dimensions per IEC 62025-1, generally with rated currents below 22 A (practically inductors no larger than about a 12 mm × 12 mm footprint).

Key topics and requirements

• Scope and applicability: Leaded and surface-mount inductors for PCB-mounted DC-to-DC converters, telecom and small switching power supplies.
• Measured limits:
  • DC saturation limited current - defined as the DC current at which inductance decreases beyond the specified limit; measured by applying a DC offset together with a small-signal AC.
  • Temperature rise limited current - defined as the DC current that causes winding/core temperature rise beyond the specified limit; measured under controlled conditions.
• Standard atmospheric and reference conditions:
  • Test ambient: 15 °C to 35 °C, relative humidity 25–75 %, air pressure 86–106 kPa.
  • Reference conditions for referee tests: 20 °C ± 2 °C, RH 60–70 %, pressure 86–106 kPa.
• Measurement techniques and jigs:
  • Measuring circuits for DC saturation testing (small-signal AC plus DC offset).
  • Temperature-rise methods including printed-wiring-board mounting, lead-wire mounting, resistance substitution and thermocouple measurement techniques.
• Documentation and conformity: Requirements for test methods, calculation procedures and details to be given in product specifications. Edition 2020 adds table/figure updates (Table 2 and Figure 2 b).

Applications and practical value

• Enables designers, procurement teams and test laboratories to compare rated currents across different manufacturers reliably.
• Supports component selection for DC-to-DC converters, switch-mode power supplies, telecommunications equipment and other PCB power designs where inductor DC current limits (saturation and heating) are critical.
• Useful for qualification testing, quality conformance inspection, and datasheet verification to ensure components meet system thermal and magnetic performance requirements.

Who should use this standard

• Inductor and magnetics manufacturers specifying rated current.
• Electronic component test labs and certification bodies.
• Power electronics designers, PCB designers and reliability/QA engineers evaluating inductor performance under DC bias.

Related standards

• IEC 62025-1 - dimensions and non-electrical characteristics for small inductors.
• IEC 60068-1 - environmental testing general guidance (referenced for atmospheric conditions).
• Other parts of the IEC 62024 series for additional electrical characteristics and measuring methods.