JPS60248037A - Electronic circuit device for optical communication - Google Patents

Abstract

PURPOSE:To reduce current consumption when a switching circuit is not in use by providing independently a power supply line to the switching circuit with respect to the power supply line to a transmission circuit and a reception circuit. CONSTITUTION:A power supply voltage VCC1 fed to a terminal 42 of a transmitter/receiver 40 is fed to a transmission circuit 22 and a reception circuit 23 via a power supply line 44 and fed to a switching circuit 24 via a power supply voltage VCC2 fed to a power terminal 43 and a power line 45. In case of the use requiring the circuit 24, when voltage VCC1, VCC2 are fed respectively to the terminals 42, 43, the circuits 22, 23, 24 are actuated. In case of the use not requiring the circuit 24, the voltage VCC1 is fed to the terminal 42 only, the voltage VCC2 is not fed to the terminal 43 and the terminal 43 is connected to a ground terminal 46. Thus, no current flows to the circuit 24 and the current consumption is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of the Invention The present invention relates to an electronic circuit device for optical communication (integrated circuit device for optical communication) used for optical communication using optical fibers.

(0) Background of the invention Generally, in optical communications using optical fibers.

Using a light-emitting and light-receiving element that has the image function of emitting and receiving light,
The method of communicating internally on both sides using a single optical fiber has the advantage of realizing a simple and economical system. Therefore, this type of communication system has been studied and developed in recent years.

As a light-emitting light-receiving element used in this single-line bidirectional communication, for example, the one shown in FIG. 3 has already been proposed (Jitsugyo Sho 58-164255). The light emitting/receiving element 1 shown here is composed of a light emitting diode section 11 and a diode section 12 with a separation groove 15 in between.

In FIG. 3, 2 is an n''-GaAs substrate, 3 is an n--
GaAs layer, 4 is p-GaAs layer, 5 is n-GaQ
, 7A, g O, 3As layer, 6 is p-Ga, 0.95A
, g O,05As active layer, 7 is p -G a O,
7Aj? 0 As1ii, 3 is a cathode electrode, 9 is an anode electrode of the light emitting diode section 11, and 10 is an anode electrode of the photodiode section 12. This light emitting light receiving element 1
As mentioned above, the application has already been filed,
Detailed explanation will be omitted.

The inventors of this application have already filed an application for an optical transmitter/receiver using the light emitting/receiving element 1 as shown in FIG. In the same figure, an optical transmitter/receiver 20 is a light emitting/receiving element 1.
and an optical communication circuit section 21, and the optical communication circuit section 21 includes a transmitting circuit 22. A receiving circuit 23 and a switching circuit 24 are included. The optical communication circuit section 21 also includes an IC (
integrated circuit), a terminal 25 for inputting the transmission signal TS, and a terminal 26 for inputting the switching signal SW. A terminal 279 for deriving a received signal; a terminal 28 and a photodiode 12 connected to the cathodes of the light emitting diode 11 and the photodiode 12;
The terminal 29 is connected to the anode of the power supply terminal 29, and the power supply terminal 30 is provided.

In this optical transmitter/receiver, the switching signal SW is ttL"'
When the transmitting signal C1 is applied to °L'', the switching circuit 24 enters the transmitting mode, and the inhibit signal C1 is applied to the receiving circuit 23 from the switching circuit 24. When the transmitting signal TS is set to °L'' in this state, the terminal 28 becomes a low potential and the inhibit signal C1 is applied to the receiving circuit 23. Current flows and emits light.Meanwhile,
When the switching signal SW is applied at ``H'', the reception mode is set, the prohibition signal C2 is applied from the switching circuit 24 to the transmission circuit 22, the terminal 28 becomes a high potential unconditionally, and when light enters the photodiode 12, the light reception mode is activated. A current flows, and this light reception signal is amplified by the reception circuit 23 and output.

Incidentally, in the optical communication circuit section 21, the stain source voltage Vao is applied to the power supply terminal 50, and is commonly supplied to the transmitting circuit 22, the receiving circuit 23, and the switching circuit 24. However, if the power supply line of the switching circuit 24 is shared with the power supply line of the transmitting circuit 22 and the receiving circuit 23 inside the IC, when the power supply voltage is applied to the transmitting circuit 22 and the receiving circuit 2, the switching circuit 24 Voltage is applied to and current flows. Therefore, even if the usage does not necessarily require prohibiting the receiving circuit 26 during transmission or disabling the transmitting circuit during receiving, current will flow through the switching circuit 24 and more current than necessary will flow through the IC. However, there are disadvantages in that the power consumption is high and the amount of heat generated is also high.

If the switching circuit 24 is not required, it may be possible to develop an IC dedicated to it, but developing and manufacturing it separately would be costly and undesirable. If possible, it is desirable to use the same type of IC for both those that use the switching circuit 24 and those that do not.

(c) Purpose of the Invention In view of the above, the purpose of the present invention is to provide an electronic circuit for optical communication that can be used both when using a switching circuit and when not, and which can consume less current when not using a switching circuit. The purpose is to provide equipment.

B) Structure and Effect of the Invention In order to achieve the above object, the electronic circuit device for optical communication of the present invention provides a power supply line for the switching circuit independently from the power supply line for the transmitting circuit and the receiving circuit. I am trying to set it up.

In the optical communication electronic circuit device of the present invention, when a switching circuit is also used, the power supply voltage is supplied not only to the transmitting circuit and the receiving circuit, but also to the switching circuit. Also, if you do not use a switching circuit.

Power is not supplied to only the switching circuit, and no current flows to the switching circuit.

According to this invention, when the switching circuit is not used, power is not supplied to the switching circuit and no current flows, so wasteful consumption and energy consumption can be reduced. You can distinguish between cases where it is necessary and cases where it is not. Therefore, there are ICs with switching circuits and ICs without switching circuits.
Compared to manufacturing both C and C separately, the cost reduction due to the mass production effect is large.

(E) Description of Embodiments FIG. 1 is a block diagram of an optical transmitting and receiving apparatus showing one embodiment of the present invention. In this figure, the same numbers as those shown in FIG. 2 indicate the same parts. That is, this optical transmitter/receiver 4° also has one light emitting and receiving element. Transmission circuit 22. It is configured to include a receiving circuit 23, a switching circuit 24, etc., and is no different from the optical transmitting/receiving device shown in the Uobushi Z diagram.

However, in this embodiment device, the power supply voltages Vcc1 and Vcc
2, the power supply voltage Vcc1 applied to the terminal 42 passes through the power supply line 44,
The power supply voltage VCC2 applied to the terminal 46 is supplied to the transmitting circuit 22 and the receiving circuit 23, and is supplied to the switching circuit 24 via the power supply line 45, that is, the switching circuit 24. A terminal 43° power supply line 45 for supplying power to the circuit 24 is connected to the transmitting circuit 22. It is provided independently and separated from that of the receiving circuit 23.

Note that 46 is a ground terminal, and 47 is a ground fin of the transmitting circuit 22 and the receiving circuit 24.

When this optical transmitter/receiver 40 is used in a manner that requires the switching circuit 24, the power supply voltages Vcc 1 and V'cc 2 are applied to the terminals 42 and 43, respectively. The receiving circuit 23 and the switching circuit 24 become operable, and in this case, the device becomes substantially the same as the device q shown in FIG.

When using a method that does not require the switching circuit 24.

Power supply voltage Vcc 1 is applied only to terminal 42, and terminal 43 is grounded. As a result, no current flows through the switching circuit 24.

In the device of the above embodiment, the power terminals 42 . Although the power supply fin 44 is shared, it may also be electrically separated. By separating them, it is possible to prevent noise from the transmitting circuit 22 from entering the receiving circuit 23.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an optical transmitting/receiving device showing one embodiment of the present invention, FIG. 2 is a block diagram showing a conventional optical transmitting/receiving device, and FIG. 6 is a cross-sectional view showing a one-chip type light emitting/receiving device. . 11: Light emitting diode, 12: Photodiode, 22:
Transmission circuit, 23: Receiving circuit. 24: Switching circuit, 44/45: Power line. Patent Applicant Tateishi Electric Co., Ltd. Agent Patent Attorney Shigeru Nakamura Figure 1 Figure 3 Figure 2

Claims (1)

[Claims] (1) A transmitting circuit that drives the light emitting element and a receiving circuit that amplifies the signal from the light receiving element. An optical communication electronic circuit device including a switching circuit that switches between a transmission mode in which the transmission circuit is operated and a reception mode in which the reception circuit is operated. An electronic circuit device for optical communication, characterized in that a power line to the switching circuit is provided independently from power lines of the transmitting circuit and the receiving circuit.