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(Once the output voltage reaches a steady state value, reduce the simspeed to 5us/s to see some beautiful ringing. I didn't add the 1nF capacitor intentionally to show ringing. I added it because EC can be crappy at times and expects the user to randomly throw in capacitors.)
A Self-Driven Synchronous Boost Converter is a Boost Converter Circuit with a Self-Driven MOSFET rectifier. A Boost Converter that uses a diode rectifier is more lossy than one that uses a MOSFET rectifier, because a MOSFET's on state resistance (and hence voltage drop) is much lower than that of a diode.
So what does Self-Driven Synchronous Rectifier mean? It is a circuit that detects the difference of voltage across the rectifier MOSFET and turns it on accordingly, without any signal from the PWM control IC that controls the main MOSFET. The advantage of using such a circuit is that it can work even if the inductor is in Discontinuous Conduction Mode. A normal Synchronous DC-DC Converter keeps one switch on when the other is off. Because of this, the inductor must be in Continuous Conduction Mode all the time in order to prevent the output capacitor from discharging through the rectifier MOSFET (since MOSFETs are a bidirectional switch, if the inductor current goes to zero and there is still time left before the control circuit turns the rectifier MOSFET off, the output capacitor, which is at a higher voltage than the input source, discharges itself into the input).
Self-Driven Rectifier: http://everycircuit.com/circuit/6669969281777664
MOSFETs used: IRF540N and IRF4905
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