摘要 |
An optical receiver of the so-called high impedance type has a photo-diode onto which the modulated light beam from an optical fiber, or received via free space, falls to produce a current in that diode. One end of the diode is coupled directly to the gate of a FET, the other end of the diode being coupled via a capacitor to the source of the FET. The FET's source and its bias resistor are on a source-connected pad. The source output of the FET is coupled via an emitter follower impedance buffer and an equalizing capacitor to a broad-band amplifier. Thus the receiver has a flat overall in-band response.
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