I think that synchronous rectification is a s good as you are going to get in this sort of application. Even a Schottky diode gets up to many tenths of a volt at moderate currents - its always better than a standard Silicon junction (Schottky uses Silicon too in normal implementations - its a technique, not a material) but its not the ideal zero resistance switch. A switched FET (or even a bipolar transistor) can give you lower voltage drop. Note also that Schottky's tend to be fairly low voltage devices (typically <= about 40 volts?). RM -----Original Message----- From: Mik Kim To: PICLIST@MITVMA.MIT.EDU Date: Wednesday, May 12, 1999 9:16 AM Subject: [OT] anything better than Schottky? >Hi all, > >This is OT, but just barely. In trying to make a switching amplifier >(original design used a PIC for testing), we were using synchronous >rectifier. Instead of its complexity, I thought maybe we can use >something like Schottky, but much better. Is there such a creature? > >Basically, we were trying to switch at 80 MHz (!) and still attain >better than 90% efficiency (inductors are the enemy!). An ideal diode >would've saved few percent, so I guess I'm wondering if there is such a >thing as a near-ideal diode (and minimal capacitance, too). We had >semiconductor fab at our disposal, so new process would be Ok. However, >a commercial product would be the best. > >Vf = 0 (or less than 0.1 volt) at 1 ampere >C = 1 pf or less at 6 volts >