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Adobe Stock / NDABCREATIVITY – stock.adobe.com Grounding provides a reference point for circuits and a path for noise dissipation. Common techniques include: X single-point grounding, which minimizes ground loops; X multi-point grounding, often used in high-frequency applications; and X ground planes, which provide low-impedance paths on PCBs. While these fundamental techniques are critical for EMI mitigation, modern power systems often require more sophisticated approaches. For example, switch-mode power supplies (SMPS) feature high- frequency operation that generates hard-to-control noise. Designers may need to take additional steps to mitigate this noise, such as incorporating both differential-mode and common-mode filters and optimizing both component placement and PCB layout. Advanced EMI Mitigation Methods Advanced EMI management leverages cutting-edge technologies and design principles to enhance EMI suppression and system performance. For example, advanced materials such as conductive polymers provide lightweight, flexible EMI shielding options. These materials are beneficial in applications where conventional metal shields are impractical, such as wearable electronics. As another example, active EMI cancellation generates an anti-noise signal to destructively interfere with unwanted EMI, proving effective in high-precision measurement equipment and communication systems that require pristine signal integrity in noisy environments. Electromagnetic bandgap (EBG) structures are engineered materials that inhibit electromagnetic wave propagation within specific frequency ranges. Integrated into PCB designs, they provide localized EMI suppression without traditional metal shields, making them valuable for high-frequency applications like 5G devices. Specialized noise suppression components, such as ferrite beads and common-mode chokes, suppress EMI in power and signal lines. Ferrite beads act as low-pass filters on power lines, while common-mode chokes block common-mode noise in data communication interfaces. Finally, advanced isolation techniques (like optical and galvanic isolation) separate sensitive circuits from noisy ones. These methods are crucial in medical devices and industrial control systems where preventing noise transfer is critical for safety and operational integrity. Advanced EMI Management in Practice A practical example of advanced EMI management is the Analog Devices LT3046 Ultra-High-PSRR Linear Regulator. Specifically intended for noise-sensitive applications, the regulator provides a stable power supply rejection ratio (PSRR), output noise, bandwidth, and load regulation across an output voltage range of 0.2V to 19V. Key specifications for the regulator include: X a high PSRR of 82dB at 1MHz, which means it can effectively reject noise on the input supply line and prevent it from coupling to the output and affecting sensitive circuitry downstream; and X an ultra-low-noise architecture with just 0.8μ V RMS noise from 10Hz to 100kHz and 2.2nV/√Hz spot noise at 10kHz, which prevents interference from being injected into the powered circuitry. While these fundamental techniques are critical for EMI mitigation, modern power systems often require more sophisticated approaches. " " LT3046 Ultra-High PSRR Linear Regulators Learn More 5 Advanced Power Solutions for Efficiency and Robustness | ADI