Optical receiver and optical transmission system
Disclosed herein is an optical receiver including: a light receiving element configured to have an anode and a cathode and generate a photocurrent dependent on received signal light; a current-voltage conversion circuit configured to be connected to the anode of the light receiving element and convert the photocurrent to a voltage signal; and a capacitive passive element configured to have a first electrode and a second electrode. The cathode of the light receiving element is connected to the first electrode of the capacitive passive element, and the second electrode of the capacitive passive element is connected to a reference potential of the current-voltage conversion circuit and the second electrode is not coupled to objects other than a reference potential terminal of the current-voltage conversion circuit.
1. An optical receiver comprising:
a light receiving element configured to have an anode and a cathode and generate a photocurrent dependent on received signal light;
a current-voltage conversion circuit configured to be connected to the anode of the light receiving element and convert the photocurrent to a voltage signal; and
a capacitive passive element configured to have a first electrode and a second electrode, wherein
the cathode of the light receiving element is connected to the first electrode of the capacitive passive element, and
the second electrode of the capacitive passive element is connected to a reference potential of the current-voltage conversion circuit and the second electrode is not coupled to objects other than a reference potential terminal of the current-voltage conversion circuit, wherein
the current-voltage conversion circuit includes
a first terminal connected to the anode of the light receiving element,
a second terminal connected to the second electrode of the capacitive passive element,
a power supply terminal connected to a power supply potential, and
the reference potential terminal connected to the reference potential, and
the second terminal is connected to the reference potential terminal via a connection path contained within the current-voltage conversion circuit,
wherein the second electrode of the capacitive passive element is directly connected to the second terminal, is indirectly connected to the reference potential terminal via the connection path, and is not directly connected to the reference potential terminal.
2. The optical receiver according to claim 1 , wherein
the current-voltage conversion circuit includes a front end part that is connected to the first terminal, the power supply terminal, and the reference potential terminal and converts a current supplied from the first terminal to a differential voltage.
3. The optical receiver according to claim 2 , wherein
the current-voltage conversion circuit has a limiting circuit to limit a level of a differential voltage output from the front end part, and
the front end part and the limiting circuit share the power supply terminal and the reference potential terminal.
4. The optical receiver according to claim 2 , wherein
the current-voltage conversion circuit has a limiting circuit to limit a level of a differential voltage output from the front end part, and
the power supply terminal and the reference potential terminal are formed for each of the front end part and the limiting circuit separately.
5. An optical transmission system comprising:
an optical transmission line configured to transmit an optical signal;
an optical signal transmitting device configured to transmit an optical signal to the optical transmission line; and
an optical signal receiving device configured to include an optical receiver that receives an optical signal transmitted in the optical transmission line and converts the optical signal to an electrical signal, wherein
the optical receiver includes
a light receiving element that has an anode and a cathode and generates a photocurrent dependent on received signal light,
a current-voltage conversion circuit that is connected to the anode of the light receiving element and converts the photocurrent to a voltage signal, and
a capacitive passive element having a first electrode and a second electrode,
the cathode of the light receiving element is connected to the first electrode of the capacitive passive element, and
the second electrode of the capacitive passive element is connected to a reference potential of the current-voltage conversion circuit and the second electrode is not coupled to objects other than a reference potential terminal of the current-voltage conversion circuit, wherein
the current-voltage conversion circuit includes
a first terminal connected to the anode of the light receiving element,
a second terminal connected to the second electrode of the capacitive passive element,
a power supply terminal connected to a power supply potential, and
the reference potential terminal connected to the reference potential, and
the second terminal is connected to the reference potential terminal via a connection path contained within the current-voltage conversion circuit,
wherein the second electrode of the capacitive passive element is directly connected to the second terminal, is indirectly connected to the reference potential terminal via the connection path, and is not directly connected to the reference potential terminal.
6. The optical transmission system according to claim 5 , wherein
the current-voltage conversion circuit includes a front end part that is connected to the first terminal, the power supply terminal, and the reference potential terminal and converts a current supplied from the first terminal to a differential voltage.
7. The optical transmission system according to claim 6 , wherein
the current-voltage conversion circuit has a limiting circuit to limit a level of a differential voltage output from the front end part, and
the front end part and the limiting circuit share the power supply terminal and the reference potential terminal.
8. The optical transmission system according to claim 6 , wherein
the current-voltage conversion circuit has a limiting circuit to limit a level of a differential voltage output from the front end part, and
the power supply terminal and the reference potential terminal are formed for each of the front end part and the limiting circuit separately.
9. The optical transmission system according to claim 5 , wherein
a first transmission line exists between the light receiving element and the current-voltage conversion circuit, and
a second transmission line is formed based on a terminal connected to the second electrode of the capacitive passive element and the reference potential of the current-voltage conversion circuit.
10. The optical transmission system according to claim 9 , wherein
the first transmission line is formed of a signal line of a first layer, and
the second transmission line is formed of a floating plane that is a second layer.
11. The optical receiver according to claim 1 , wherein
a first transmission line exists between the light receiving element and the current-voltage conversion circuit, and
a second transmission line is formed based on a terminal connected to the second electrode of the capacitive passive element and the reference potential of the current-voltage conversion circuit.
12. The optical receiver according to claim 11 , wherein
the first transmission line is formed of a signal line of a first layer, and
the second transmission line is formed of a floating plane that is a second layer.
13. An optical receiver comprising:
a current-voltage conversion circuit connected to an anode of a light receiving element, the light receiving element being configured to generate a photocurrent dependent on received signal light and the current-voltage conversion circuit being configured to convert photocurrent from the light receiving element to a voltage signal; and
a capacitive passive element including a first electrode and a second electrode, the first electrode being connected to a cathode of the light receiving element, wherein
the current-voltage conversion circuit includes
a first terminal connected to an anode of the light receiving element,
a second terminal connected to the second electrode of the capacitive passive element,
a power supply terminal connected to a power supply potential, and
the reference potential terminal connected to the reference potential, and
the second electrode of the capacitive passive element is connected to the reference potential terminal of the current-voltage conversion circuit via a connection path contained within the current-voltage conversion circuit,
wherein the second electrode of the capacitive passive element is directly connected to the second terminal, is indirectly connected to the reference potential terminal via the connection path, and is not directly connected to the reference potential terminal.
14. The optical receiver according to claim 13 , wherein
the second electrode of the capacitive passive element is connected only to the reference potential terminal of the current-voltage conversion circuit.
15. The optical receiver according to claim 14 , further comprising
a first transmission line connecting the light receiving element and the current-voltage conversion circuit, and
a second transmission line connecting the second electrode of the capacitive passive element and the reference potential of the current-voltage conversion circuit.
16. The optical receiver according to claim 15 , wherein
the first transmission line is formed of a signal line of a first layer, and
the second transmission line is formed of a floating plane that is of a second layer.
17. The optical receiver according to claim 13 , wherein
the current-voltage conversion circuit includes a front end part that is connected to the first terminal, the power supply terminal, and the reference potential terminal and converts a current supplied from the first terminal to a differential voltage.
18. The optical receiver according to claim 17 , wherein
the current-voltage conversion circuit has a limiting circuit to limit a level of a differential voltage output from the front end part, and
the front end part and the limiting circuit share the power supply terminal and the reference potential terminal.
19. The optical receiver according to claim 17 , wherein
the current-voltage conversion circuit has a limiting circuit to limit a level of a differential voltage output from the front end part, and
the power supply terminal and the reference potential terminal are formed for each of the front end part and the limiting circuit separately.
20. An optical transmission system comprising:
an optical transmission line configured to transmit an optical signal;
an optical signal transmitting device configured to transmit an optical signal to the optical transmission line; and
an optical signal receiving device including the optical receiver according to claim 13 .