| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical receiver capable of accurately receiving data over a wide signal light intensity and the circuit scale of which can be downsized. <P>SOLUTION: The optical receiver 1 includes a TLA circuit 2, a differential output circuit 3, an averaging circuit 4, and a photodiode 11. The TLA circuit 2 converts an optical current I from the photodiode 11 into a received signal S being a voltage signal. The averaging circuit 4 provides an average of the received signals S to the differential output circuit 3 as a reference voltage Vref. The differential output circuit 3 generates differential signals Sin+, Sin- on the basis of the received signal S from the TLA circuit 2 and the reference voltage Vref from the averaging circuit 4. The TLA circuit 2 includes a gain variable means (FET 23) for passively changing a conversion gain of the TLA circuit 2 depending on the magnitude of the optical current I. The time constant of the averaging circuit 4 is made variable according to a control signal Sc. <P>COPYRIGHT: (C)2008,JPO&INPIT |
