Systems and methods to improve photodiode amplification operation in photonic receiver
View Patent ↗In part, in one aspect the disclosure relates to an optical transducer such as an optoelectronic transducer. In many embodiments, the optoelectronic transducer may include a semiconductor substrate; a first photodiode comprising a first anode and first cathode; and a second photodiode comprising a second anode and a second cathode, wherein the first photodiode and the second photodiode comprise one or more semiconductor structures or layers disposed on or in the semiconductor substrate, wherein the first anode and the first cathode are electrically coupled to and reverse biased by one or more transimpedance amplifiers; wherein the second anode and the second cathode are electrically coupled to and reverse biased by one or more transimpedance amplifiers.
1 . An optical transducer comprising:
a first photodiode comprising a first anode and first cathode; and
a second photodiode comprising a second anode and a second cathode,
wherein the first anode is coupled to a first transimpedance amplifier (TIA) and the first cathode is coupled to a second TIA, wherein the first and second TIAs are configured to reverse bias the first photodiode;
wherein the second anode is coupled to a third TIA and the second cathode is coupled to a fourth TIA, wherein the third and fourth TIAs are configured to reverse bias the second photodiode.
2 . The optical transducer of claim 1 , wherein each of the first, second, third, and fourth TIAs is a single ended transimpedance amplifier.
3 . The optical transducer of claim 1 , wherein of the first, second, third, and fourth TIAs are part of two differential transimpedance amplifiers, wherein each of the differential transimpedance amplifiers comprises two inputs, wherein there is a 180 degree phase offset between the two differential transimpedance amplifiers.
4 . The optical transducer of claim 3 , wherein a first input of one of the differential transimpedance amplifiers is electrically coupled to the first anode of the first photodiode, wherein a second input of one of the differential transimpedance amplifiers is electrically coupled to the second cathode of the second photodiode.
5 . The optical transducer of claim 1 , further comprising a summing circuit in electrical communication with the first, second, third, and fourth TIAs.
6 . The optical transducer of claim 1 , wherein the reverse biasing of the first photodiode increases signal to noise ratio of the optical transducer by a value that ranges from about 0.5 dB to about 3 dB.
7 . The optical transducer of claim 1 , wherein one or more electrical connections between the first photodiode and first and second TIAs are wirebonds.
8 . The optical transducer of claim 1 , wherein the first photodiode and the second photodiode comprise one or more semiconductor structures or layers disposed on or in a semiconductor substrate, wherein capacitance of the semiconductor substrate ranges from about 15 Femtofarads to about 30 Femtofarads.
9 . The optical transducer of claim 8 , wherein the semiconductor substrate is silicon, silicon on insulator, silicon oxide or silicon nitride.
10 . The optical transducer of claim 1 , wherein the first, second, third, and fourth TIAs are part of one four quadrant TIA, wherein the four quadrant TIA comprises one or more complementary metal-oxide-semiconductor inverter TIAs and one or more voltage to current converters.
11 . The optical transducer of claim 1 , further comprising a photonic integrated circuit, the photonic integrated circuit comprising the first photodiode, the second photodiode, and the first, second, third, and fourth TIAs.
12 . The optical transducer of claim 1 , further comprising a high pass filter in electrical communication with the first photodiode and the second photodiode.
13 . The optical transducer of claim 1 , wherein electrical connections to terminals to which the first, second, third, and fourth TIAs connects are symmetric.
14 . An optical transducer comprising:
a transimpedance amplifier comprising first, second, third, and fourth electrical terminals;
a semiconductor substrate;
a first photodiode comprising a first anode and first cathode; and
a second photodiode comprising a second anode and a second cathode,
wherein the first anode is coupled to the first terminal and the first cathode is coupled to the second terminal and the second anode is coupled to the third terminal and the second cathode is coupled to the fourth terminal,
wherein the first anode and first cathode are reversed biased by the transimpedance amplifier;
wherein the second anode and the second cathode are reversed biased by the transimpedance amplifier.
15 . An optical transducer comprising:
one or more transimpedance amplifiers (TIAs); and
a photodiode comprising an anode and a cathode,
wherein the anode is coupled to the one or more TIAs and the cathode is coupled to the one or more TIAs, wherein the one or more TIAs are configured to reverse bias the photodiode.
16 . The optical transducer of claim 15 , wherein the one or more TIAs comprises a single TIA coupled to both the anode and the cathode.
17 . The optical transducer of claim 15 , wherein the one or more TIAs comprises at least two TIAs, wherein the anode is coupled to a first one of the at least two TIAs and the cathode is coupled to a second one of the at least two TIAs.
18 . The optical transducer of claim 17 , further comprising:
a second photodiode comprising a second anode and a second cathode, wherein the second anode is coupled to the first one of the at least two TIAs and the second cathode is coupled to the second one of the at least two TIAs, wherein the at least two TIAs are configured to reverse bias the second photodiode.