It’s in German so switch to English subs or read the ai summary below.
The biggest plague of electronics: Common Mode disturbances caused by switch-mode power supplies
AI generated summary
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Electrical engineering plagued by Common Mode (Gleichtakt) disturbances, unnoticed by many.
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Common Mode disturbances in switch-mode power supplies can cause significant harm, including destructive voltages to sensitive components.
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Common Mode disturbances originate from parasitic capacities within switch-mode power supply windings or cooling bodies.
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Switch-mode power supplies (USB chargers, laptop chargers) have deceptive voltages not directly measurable on the output.
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To detect Common Mode disturbances, a multimeter must be set to AC voltage measurement, which can reveal unexpected high voltages with respect to ground. Up to 100V AC Common Mode disturbances!
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Such disturbances are present on laptops and various chargers, potentially damaging connected sensitive equipment through USB or other interfaces.
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Damage can occur when working with hardware tools or development boards (e.g., Raspberry Pi, STM32, FPGA) if the ground potential is affected by laptop-supplied voltages.
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Grounding or using a benchtop power supply does not safeguard against Common Mode disturbances; connecting the negative terminal to ground is necessary to protect hardware.
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Working with desktop PCs avoids Common Mode disturbances due to the grounded chassis.
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Devices with two-prong plugs lacking ground connection (e.g., certain laptops, monitors, game consoles) are more susceptible to Common Mode disturbances.
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Devices with a three-prong plug ensuring proper grounding (e.g., PC power supplies) are safer from Common Mode disturbances.
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Awareness of Common Mode disturbances is necessary, especially for beginners working with laptops or sensitive equipment, to prevent damaging valuable hardware.
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The video urges sharing of information about Common Mode disturbances to help others avoid costly hardware damage.
