In a receiver in an optical communication system, a photodiode (PD) converts an optical signal into a current signal. In addition, a transimpedance amplifier (TIA) connected to the PD converts the current signal into a voltage signal and amplifies it, and sends the signal to a next stage.
Conventionally, when constructing such an optical receiving circuit, an anode of a PD and a TIA are connected by wire bonding, and a cathode of the PD is grounded via a chip capacitor. There are several methods for supplying an electrical power to a PD, such as a method for separately supplying an electrical power to each of a PD and a TIA and a method for supplying an electrical power from a TIA to a PD. For reducing the number of electrical power sources and/or the number of electrical power source pads, it is desirable to supply an electrical power from a TIA to a PD.
In such an optical receiving circuit, a wiring for connecting a PD and a TIA has a large effect on a characteristic of the optical receiving circuit and, as a result, an eye pattern of a voltage signal outputted from the TIA may be deteriorated.
USPTO Backgrounds
USPTO Backgrounds