Experimental SMPS Topology Selector
Suggested Topologies
Disclaimer: The suggestions provided by this tool are based on simplified criteria and general power electronics principles. They serve as a starting point for design and may not be exhaustive or perfectly optimal for all specific applications. Always conduct thorough research, detailed analysis, and practical testing to select the most suitable topology for your unique requirements.
Note: These suggestions are based on common design practices and simplified ideal conditions. Always consider specific application requirements, component availability, efficiency, and cost in your final design.
Simplified Circuit Diagram:
Note: This is a simplified, conceptual diagram for understanding.
Understanding SMPS Topologies
Switched-Mode Power Supplies (SMPS) use various circuit configurations, known as topologies, to efficiently convert electrical power. The choice of topology depends heavily on input/output voltage relationship, power level, isolation requirements, and cost.
Non-Isolated Topologies:
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Buck (Step-Down): Produces an output voltage lower than its input. Simple, high efficiency for step-down. Best for fixed step-down conversion at low to medium power (typically up to ~200W).
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Boost (Step-Up): Produces an output voltage higher than its input. Simple, high efficiency for step-up. Best for fixed step-up conversion at low to medium power (typically up to ~200W).
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Buck-Boost (Inverting): Output voltage can be higher or lower than the input, but it’s always of opposite polarity. Versatile for wide input voltage variations. Low to medium power (typically up to ~100W).
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SEPIC (Single-Ended Primary-Inductor Converter): Output voltage can be higher or lower than the input, and it’s non-inverting. Can step-up or step-down. Offers true shutdown (output goes to 0V). Often used where input voltage varies widely around the output voltage, or in battery applications. Low to medium power (typically up to ~100-150W). Can be made isolated with a coupled inductor.
Isolated Topologies:
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Flyback: Most common isolated topology for low to medium power (< 150-200W). Simple, low component count, easy to implement multiple outputs with auxiliary windings. Output ripple can be higher.
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Forward: Used for medium power (100W – 500W). More efficient than Flyback at similar power levels. Requires a transformer reset mechanism (e.g., demagnetizing winding). Can provide multiple outputs.
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Push-Pull: Medium to high power (200W – 1kW+). Utilizes both halves of the transformer’s magnetic cycle, leading to smaller transformer size for given power. Requires careful control to prevent core saturation.
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Half-Bridge: High power (300W – 1kW+). Uses two switches and two capacitors, reducing voltage stress on switches compared to Push-Pull. Good efficiency.
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Full-Bridge: Very high power (500W – multiple kW). Uses four switches, offering highest power capability and best efficiency among traditional isolated topologies. Complex control.
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PSFB (Phase-Shifted Full Bridge): High power (500W – multiple kW). A variation of the Full-Bridge that achieves Zero Voltage Switching (ZVS) over a wide load range, improving efficiency, especially at high frequencies. Complex control.
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LLC Resonant: High power (500W – multiple kW). Achieves ZVS and Zero Current Switching (ZCS) for high efficiency, especially beneficial for applications with wide load variations or specific voltage conversion ratios. Complex design and optimization.
The actual power ranges are approximate and depend on components, cooling, and specific design choices.