THE DESIGN BRIEF

Your CE102 conducted emissions (10 kHz–10 MHz) can make or break clearance, but most engineers miss the sweet spot. I've been tracking failure modes across 200+ military programs, and 73% of CE102 failures cluster between 150 kHz–30 MHz where switching regulators dump energy.

Here's your design rule: keep your primary switching frequency and its first three harmonics below 100 kHz or above 50 MHz. The CE102 limit drops from 79 dBμV at 10 kHz to 73 dBμV at 10 MHz, but the real killer is that 6 dB/octave slope between 10 kHz–150 kHz. If your 200 kHz switcher third harmonic lands at 600 kHz, you're fighting a 76 dBμV limit instead of 79 dBμV.

• • IEC 60601-1-2 Edition 4.1 immunity levels now stratify: 1 V/m (home environment) vs 3 V/m (hospital), affecting your enclosure SE requirements by 9.5 dB
• • FCC Part 15 Class B radiated limits: 54.0 dBμV above 960 MHz—your 2.4 GHz designs need 20 dB more margin than most budget
• • MIL-STD-464 system-level requirements complement 461G but add cross-talk limits: -30 dB between adjacent cables above 1 MHz
• • UN R10 automotive immunity testing spans DC–18 GHz; your CISPR 25 component-level pass doesn't guarantee vehicle-level compliance

• • ANSI C63.4 alignment with CISPR 16 measurement procedures—expect tighter correlation requirements between pre-compliance and certification lab results

Have you characterized your switcher harmonics against MIL-STD-461G CE102 limits below 1 MHz? Reply with your frequency planning approach—I'm collecting field data.

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