In a typical AC-DC switch mode power supply (SMPS), the AC mains is rectified and filtered to feed a power factor correction (PFC) stage. Then, by means of high-frequency modulation techniques – sometimes in excess of 1 MHz to reduce size of transformers and inductors – it is then delivered to a DC load with the desired voltage and current ratings. To find the best solution for their applications, designers have to choose the best power topology – fly-back, buck, or quasi-resonant – or the implementation – based on highly integrated converters or with discrete power switches and controllers – or even decide to use an advanced digital implementation.
Buck and buck-boost converter
Off-line converters based on buck, or step-down, and buck-boost, or step-down/up, topologies convert the mains to a regulated DC output, either positive or negative, without the need for an isolation transformer by modulating the duty cycle of the po
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Flyback converter
In its various implementations including primary side and secondary side regulation, fixed switching frequency or quasi resonant operation, an isolated or non-isolated flyback topology is most often found in off-line converters for an output power ra
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LLC resonant converter
The LLC converter is a resonant inverter with three reactive elements where the DC input voltage is turned into a square wave by a switch network arranged as either a half- or full-bridge to feed the resonant LLC tank that effectively filters out har
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PFC converter - Single phase input
Power Factor Correction aims at shaping input current to be as sinusoidal as possible, in order to reduce harmonic distortion and its associated losses, and bring power factor close to one in AC circuits. Placed at the front end of relatively high-p
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PFC converter - Three phase input
Power Factor Correction is a technique of shaping input current to be as sinusoidal as possible to reduce harmonic distortion and associated losses and in-phase with input voltage in an AC circuit to have a power factor close to one. Placed as a fron
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PS ZVS FB converter
In a phase-shifting, zero voltage switching full-bridge converter, the two legs of the full-bridge are switched with two square waves whose phase shift is modulated by the converter’s control loop and the resulting square wave is fed into the primary
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Two switch flyback converter
In a two-switch flyback topology, a high-side power MOSFET – placed between the input voltage rail and the transformer – and snubber diode are added to help overcome the limitations of conventional flyback topology as the overall voltage stress is eq
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Two switch forward converter
In a two-transistor forward the two transistors of the primary are switched on and power is transferred to the secondary winding of the transformer and then to the output capacitor and the load. When switched off, the diodes in the primary clamp the
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Our products and solutions
Whatever their choice, the right semiconductor products are key to meeting their specific design targets. ST’s broad product portfolio includes highly-integrated AC-DC converters and controllers, silicon and silicon carbide (SiC) power MOSFETs and rectifiers, IGBTs, protection ICs and specifically designed digital controllers and STM32 microcontrollers. We also provide a comprehensive range of hardware and software evaluation and development tools including our eDesignSuite that helps engineers design high efficiency power supplies and converters.