JPS5846071B2 - semiconductor integrated device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a semiconductor integrated device.

For example, a conventionally known semiconductor integrated device that amplifies a minute DC signal such as a signal from a thermocouple has a power supply terminal to which power is supplied to operate the device and an output terminal to which the amplified output is sent. .

If the grounding level of the power supply connected to this power supply terminal and the load connected to the output terminal is not sufficiently considered in relation to the grounding level of the input signal, ground current may flow or the signal or power transmission line may The problem is that noise may be mixed in, and there are significant restrictions on how it can be handled.

The present invention is a semiconductor integrated device for amplifying low-level electrical signals, and is aimed at eliminating the drawbacks of the conventional devices as described above. One feature is that it uses signals.

FIG. 1 is a cutaway perspective view of essential parts showing an embodiment of the present invention.

Here, an example is shown in which the semiconductor integrated circuit 2 is enclosed in a metal case 1 such as a TO-5, but the present invention is not limited thereto.

In the semiconductor integrated circuit 2, 3 is a semiconductor substrate made of silicon or the like, on the surface of which an amplifier circuit (electronic circuit) section 4, a light receiving section 5, and a light control section 6 are formed.

Reference numerals 41 and 42 indicate input terminals for supplying input signals to the amplifier circuit section 4.

The light receiving section 5 has a function as a photoelectric conversion means such as a solar cell, for example, and the electrical energy converted here is supplied to the amplifier circuit section 4 to operate each circuit that constitutes the amplifier circuit section 4.

The light control section 6 is a light control element such as a light emitting diode or a liquid crystal, and the intensity of light or the transmittance (or reflectance) of the light is controlled according to the output signal from the amplifier circuit section 4.

Reference numeral 7 indicates a light feeding fiber whose one end is coupled to the light receiving section 5, 8 indicates an output optical fiber whose one end is coupled to the light control section 6, and the other ends of both are optical fiber coupling terminals fixed to the case substrate 10. It is connected to 70 and 80.

Reference numerals 71 and 81 indicate optical fiber transmission lines, one end of which is coupled to an external device (not shown).

FIG. 2 is an electrical connection diagram showing an example of the semiconductor integrated circuit 2. As shown in FIG.

In the figure, the light receiving section 5 includes a plurality of solar cells 51, 52,
... are connected in series, and each solar cell is irradiated with light emitted from one end of the light feeding fiber 7.

It is assumed that optical energy is supplied from the other end of the optical fiber 7 from another device (not shown).

+V, VS1TVs2. -V conceptually represents a power supply terminal that supplies a DC voltage obtained from the light receiving section 5, respectively.

O8C is an oscillator, A1. A2 is an amplifier, and CO is a comparator, both of which are formed in the amplifier circuit section 4. Their respective power terminals +V and -V are connected to the power terminals +V and -V of the light receiving section 5, and each solar cell 51 , 52 . . .

In addition, a power supply ■s1 connected to one end of the resistor R1, a resistor R
A power source s2 connected to one end of s is also obtained from the light receiving section 5.

For example, the minute signal ei from the thermocouple TH is input to the input terminal 4L.
After being amplified by an amplifier A1, the signal is printed to an input terminal of an integrator IN constituted by an amplifier A2 and a capacitor C via an input resistor Ri.

In addition, the input end of this integrator IN is connected to an input resistor Ri5: a clock pulse Pc from an oscillator O8C, and a reference voltage -■s2 via a resistor Rs and a FET switch SO.
is marked.

The output signal of the integrator IN is marked at the input terminal of the comparator CO, and is compared with the zero potential, and the output signal of the FE is determined according to the result of this comparison.
Turn on and off the T switch SO, and check whether the reference electrostrictive -Vs2 is connected to the input terminal of the integrator IN or not.
A pulse width signal corresponding to the minute signal ei and whose repetition period is maintained at the period of the clock pulse is obtained from the output terminal of the comparator CO.

A light emitting diode 6 serving as a light control section is connected to the output end of the comparator CO1, and emits light in accordance with the pulse width output signal of the comparator CO.

One end of the output optical fiber 8 is coupled to the light emitting diode 6, and light with a pulse width corresponding to the minute signal ei from the light emitting diode 6 is transmitted through the output optical fiber 85 to an external device (not shown). It is derived from

In a device configured in this way, the operating power for the various circuits formed in this device is supplied from the light receiving section formed within this device, and the output signal of this device is output as an optical signal. Therefore, there is no need for electrical power supply terminals or output terminals, and there is no need to connect to power supply lines or output lines, so there is no need to worry about various types of noise mixing from these lines or grounding levels. It has characteristics.

FIG. 3 is a perspective view of essential parts showing another embodiment of the present invention.

In this embodiment, a single fiber 9 is used as both the light supply fiber and the output optical fiber in the embodiment shown in FIG. It is coupled to a light branching portion 92 formed on the substrate 3.

FIG. 4 is an electrical connection diagram of the device shown in FIG.
Here, a half mirror and a full mirror are used, and the light sent from the dual-purpose fiber 9 is branched into a light receiving section 5 and a light control section 6.

Here, the light control section 6 has a reflectance equal to that of the analog amplifier circuit A.
A liquid crystal controlled by a signal from C is used, and is irradiated with light from a light branching section 92, and the reflected light here is made to enter one end of the dual-purpose fiber 9 as output light.

The amplifier circuit section 4 here includes an analog amplifier circuit AC,
A digital circuit DC is formed, and these are connected to the light receiving section 5.
The digital circuit DC outputs digital signals to output terminals 43 and 44.

Therefore, the digital indicator D is connected to this output terminal 43.44.
Digital measurement values can be obtained by connecting I.

5 and 6 are electrical connection diagrams of still another embodiment of the present invention.

In the embodiment shown in FIG. 5, a liquid crystal whose light transmittance changes depending on the output signal from the analog amplifier circuit AC is used as the light control section 6.

The output light that has passed through the liquid crystal 6 passes through the fiber 93,
is input to the dual-purpose fiber 9 by the half mirror 94,
sent to other devices.

In the embodiment shown in FIG. 6, the light control section is composed of two liquid crystals 61 and 62 whose light transmittances vary differentially depending on the output signal of the amplifier circuit AC.

The two types of output light that have passed through each liquid crystal 61 and 62 are sent to another device via an output optical fiber 8 and 81 that is configured by bundling two transmission lines.

When the output light is transmitted as two types of differential signals in this way, other devices that receive this output light can perform appropriate processing such as calculating the difference between these two types of signals to control the light control unit and It has the advantage of not being affected by changes in characteristics in optical fibers and the like.

FIG. 7 is a cutaway perspective view of a main part of another embodiment of the present invention, and FIG. 8 is an electrical connection diagram.

In this embodiment, an analog circuit section 4A that inputs an electric signal from, for example, a thermocouple TH, and a digital circuit section 4D that outputs a digital signal (including a pulse width signal) to, for example, a digital value display DI are provided on the semiconductor substrate 3. .

A light receiving section 5 and a light control section 6 are formed, and one end of a light supply/output fiber 9 is branched into two parts and coupled to the light receiving section 5 and the light control section 6.

In the connection diagram of FIG. 8, the analog circuit section 4A consists of an amplifier A1 and a reference junction compensation circuit TR, and the digital circuit section 4D consists of an analog pulse conversion circuit D1 and the signals necessary to display the pulse input signal as a digital value. It consists of a display circuit D2 that converts the

Digital signals are output from the display circuit D2 via output terminals 43-46.

The light control unit 6 here uses, for example, lithium niobate (L
iNb03) layer 63, a polarizing plate 64 for polarizing the light from the fiber 9 to the lithium niobate layer 63;
Reflector 65 and layer 6 that reflect the light that has passed through layer 63
This is an optical modulator having an electrode plate 66 provided at 3.

When the output signal from the analog pulse conversion circuit D1 is applied to the electrode plate 66 of the optical modulator, the light passing through the layer 63 is polarized in accordance with the output signal, and the output signal causes the light to be polarized at one end of the fiber 9. An optical signal whose intensity is modulated is input.

Note that the other end of the transmission fiber 91 is connected to 2 in another device.
On one side, there is a high-power light source for supplying optical energy, such as a light emitting diode or a laser diode Ls.
is coupled to the other side, and a photoelectric conversion element for light reception, such as a photodiode PT, is coupled to the other side.

In each of the above embodiments, there is a gap between one end of the light feeding fiber 7 and the light receiving section 5, between one end of the output optical fiber 8 and the light control section 6, between the light branching section 92 and the light receiving section 5, and between the light receiving section 5 and the light control section. 6 are optically coupled to each other by a transparent, low-viscosity, strength-setting matching agent, etc., so that light propagation can be carried out efficiently.

In addition, at the optical fiber coupling terminal 70, 80 or 90, optical fibers from other devices are optically coupled, and the end faces of both fibers are treated so that the optical coupling between the two fibers is also performed efficiently. .

In each of the above embodiments, as the optical signal output from the light control section 6, in addition to a pulse width signal, a frequency signal, a digital code signal, a light intensity signal, etc. can be used.

As described above, according to the present invention, it is possible to realize a semiconductor integrated device that does not require consideration of the ground level and noise of input signals.

[Brief explanation of drawings]

Fig. 1 is a cutaway perspective view of essential parts showing one embodiment of the present invention;
3 is a perspective view of essential parts showing another embodiment of the present invention, FIG. 4 is an electrical connection diagram thereof, and FIGS. 5 and 6 are further embodiments of the present invention. FIG. 7 is a cutaway perspective view of a main part of still another embodiment of the present invention, and FIG. 8 is an electrical connection diagram thereof. DESCRIPTION OF SYMBOLS 1... Case, 2... Semiconductor integrated circuit, 3... Substrate, 4... Amplifier circuit section, 5
...... Light receiving section, 6... Light control section, 7...
... Light supply fiber, 8 ... Output optical fiber.

Claims (1)

[Claims] 1. An electronic circuit on a semiconductor substrate that receives a minute electrical signal as an input signal, a photoelectric conversion section that converts optical energy into electrical energy, and an optical signal responsive to an output signal from the electronic circuit. an optical fiber having one end coupled to the photoelectric conversion section and supplying optical energy for operating the electronic circuit via the photoelectric conversion section; A semiconductor integrated device comprising an optical fiber coupled at one end to transmit an optical signal generated by the optical control section. 2. The semiconductor integrated device O' according to claim 1, in which the optical fiber optically coupled to the photoelectric conversion section and the optical fiber optically coupled to the light control section are separate. 2. The semiconductor integrated device according to claim 1, wherein the optical signals are two types of differential signals. 4. The semiconductor integrated device according to claim 1, which uses a light emitting diode as a light control element. 5. The semiconductor integrated device according to claim 1, which uses an optical modulator whose light transmittance or reflectance changes as a light control element.