Fast transistor as a diode

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htg

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I would like to rectify 200 MHz. The only diode that I found (Motorola's MBD301) is a low power component (30V, 100mA, 1.5pF, 100ps Trr).
Somebody suggested connecting collector to base of a fast transistor. What transistors could I use to get significant power and good rectification efficiency?
Is it better to use a bipolar transistor or a JFET?
 

I would expect better results from the MBD301 schottky diode (or various other types)
than from a Si junction diode (including transistor Cbe).
 

    H

    htg

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Fast transistors are only fast until you get into saturation; then
they slow down plenty and more importantly, store a lot of charge.
Connecting them as inverse transdiodes is likely to put them into
saturation when you get to any decent current.

"No minority carriers" is a good rule of thumb for you.
 

    H

    htg

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So is MBD301, 30V,100mA,1.5pF, 100ps Trr, the best thing there is? I would like more power.
 

You could look at power Schottky diodes (for switching supplies, etc.)
in terms of If/CJO as a figure of merit.
 

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