Method for stabilizing voltage in electrical circuits

Abstract

FIELD: electric circuitry.SUBSTANCE: invention which can be used to create a reference voltage in adjustable power supplies, a stable output voltage during input voltage fluctuations and load changes, as well as for overvoltage protection in low-power devices. The essence of the invention is that the method for stabilizing voltage in electrical circuits includes the use of a p-n-junction of an optoelectronic device with reverse connection, the effect of electromagnetic radiation of the optical range on the crystals of photodetectors and photodetectors of optrons, the absorption of electromagnetic radiation by the p-n-junction of the crystals of photodetectors and photodetectors of optrons, the creation in the region of the p-n-junction of an electric field with a voltage equal to the breakdown voltage, depending on the intensity of the effect of optical radiation, and the regulation of current and voltage is carried out using optical radiation.EFFECT: low-voltage stabilizing diode with a stabilization voltage of less than 1.8 V.6 cl, 4 dwg

Description

[0001] The method of operating as a zener diode is applicable to optoelectronic devices such as photodetectors and optocouplers. The invention relates to radio engineering and can be used in household and industrial electronic equipment to generate a stable output voltage or reference voltage in regulated power supplies with values ​​less than 1.8 V.

[0002] Photodetectors are semiconductor devices that convert light energy into electrical energy. Photodetectors include photodiodes, phototransistors, and photothyristors. Photodetectors operate based on the internal photoelectric effect, where photons of light striking a semiconductor generate electron-hole pairs. These charge carriers are then separated by the electric field of the p-n junction, generating a photocurrent proportional to the intensity of the incident light. Photodetectors are characterized by a high response speed, making them indispensable for applications requiring rapid detection of changes in illumination. Photodetectors are compact, energy-efficient, and highly sensitive over a specific spectral range, depending on the semiconductor material. There are various types of photodiodes, including p-n, PIN, and avalanche.Pn photodiodes are simple in design but have lower sensitivity than PIN diodes, which have an intrinsic conductivity layer (I-layer) between the p and n regions, increasing the light absorption area and reducing capacitance. Avalanche photodiodes (APDs) provide internal photocurrent amplification through avalanche multiplication of charge carriers, significantly increasing their sensitivity but requiring a higher bias voltage. Silicon, germanium, and gallium arsenide phototransistors, which are sensitive to radiation in the visible and infrared ranges, are also common in practical electronics.

[0003] Photodetectors are used: 1) in fiber optic communications to detect light signals, enabling data transmission over long distances; 2) in automatic lighting control systems, such as streetlights that turn on when it gets dark; 3) in various devices for measuring light levels, such as photocells for automatically controlling the brightness of screens; 4) in security alarms and motion detection systems, where their sensitivity to light allows changes in the environment to be detected; 5) in medical diagnostic devices, such as pulse oximeters, which measure oxygen levels in the blood; 6) in spectrometers for analyzing the composition of materials from their light spectra; 7) in digital cameras and other image capturing devices; 8) in driver assistance systems, such as adaptive lighting and parking systems;9) in scientific experiments related to photonic technologies and in laboratory installations for measuring light intensity.

[0004] Optocouplers are electronic devices that use light to transmit signals between their input and output, while providing electrical isolation. Optocouplers consist of an emitter (LED or laser) and a photodetector (diode, transistor, or thyristor), all housed in a single housing. Optocouplers provide electrical isolation between input and output, allowing for the safe transfer of signals between different circuits, especially when they operate at different voltages. Optocouplers are used in control circuits, power supplies, communication systems, and to protect sensitive components from high voltages and interference. Additionally, optocouplers are used to transmit signals between various units of microprocessor systems, in automation and industrial electronics, and to protect against interference and overvoltage.

[0005] A common drawback of all known methods of operation of photodetectors and optocouplers is that they do not provide for the principle of stabilizing current and voltage using reversible electrical breakdown of the pn junction under the influence of optical radiation.

[0006] A zener diode is a semiconductor device designed to stabilize voltage in electrical circuits.There are different types of zener diodes, each with its own characteristics and applications: 1) Zener diode; 2) Silicon-based zener diodes, which have high stability and operate over a wide temperature range; 3) Germanium-based zener diodes are less common, but can be used in specific applications where high sensitivity is important; 4) Temperature-stabilized zener diodes have special designs to minimize the effect of temperature on their performance; 5) High-breakdown voltage zener diodes are designed to work with high voltage values, making them useful in power devices; 6) Low-breakdown voltage zener diodes; 7) Shunt zener diodes are used to protect circuits from overvoltage, triggering when a set threshold is exceeded; 8) Adjustable voltage zener diodes allow the output voltage to be adjusted within certain limits.

[0007] The prototype of the invention is a controlled zener diode, which is a small semiconductor integrated circuit based on a differential cascade, in which the output voltage can be changed depending on the control signal (e.g., TLV431, NCV431, SCV431, Low voltage precision adjustable shunt regulator, Datasheet; TL431A, B Series, NCV431A, B Series, SCV431A, Programmable shunt regulator diodes, Datasheet). This allows for more flexible voltage control in electrical circuits. Zener diodes of this type are often used in circuits that require voltage regulation, for example, in power supplies, protection circuits, and voltage stabilization. A controlled zener diode is functionally similar to a conventional Zener diode, but contains a control circuit based on several bipolar or field-effect transistors.

[0008] The main disadvantages of industrially produced p-n junction zener diodes are the lack of regulation and the ability to obtain voltages less than 1.8 V. The disadvantages of controlled single-case zener diodes include temperature-dependent logarithmic feedback, electrical noise, parasitic reactive or capacitive properties and fairly long transient processes. There are known patents for various circuits of electrically controlled stabilizers SU 1483442 A1, SU 905808 A1, RU 105035 U1, US 6703813 B1, CN 114077277 B, US 8704506 B2, CN 112073050 B, US 20120187927 A1 and others. Zener diodes with optical control are unknown.

[0009] The problem solved by the invention: creating a controlled zener diode with an operating voltage of less than 1.8 V.

[0010] The problem is solved by using a photodetector with an external source of optical radiation or an optocoupler as a zener diode.

[0011] The invention is implemented as follows. Instead of a zener diode, pn-junctions of an optocoupler photodetector or a separate photodetector (when reverse-connected) are used, in which electromagnetic radiation in the optical range is converted into electric current. The operating principle is based on photoconductivity, the generation of charge carriers under the influence of light and the creation of an electric field in the pn-junction region. When a photon hits a semiconductor crystal, it can be absorbed in the pn-junction region. If the photon energy is sufficient to excite an electron (this usually occurs if the photon energy exceeds the band gap of the semiconductor), the electron moves from the valence band to the conduction band. Thus, when electromagnetic radiation is absorbed, electron-hole pairs are created. The electric field created in the pn-junction region facilitates the separation of electron-hole pairs.Electrons move toward the n-type region, and holes toward the p-type region. The movement of charge carriers creates an electric current through the structure at a voltage equal to the breakdown voltage. The breakdown current and voltage depend on the optical signal level and can therefore be controlled using an optocoupler emitter or an external light source for the photodiode.

[0012] The following application examples of the invention are highlighted. The proposed method for operating optoelectronic devices can be used to maintain a constant output voltage or current in low-power power supplies, which is especially important for sensitive electronic devices. The proposed solution can be used to create simple generator and regulator circuits that provide a specified output voltage, as well as filters to limit signal amplitude and protect against high-frequency interference. A separate application area is measurement technology, which requires a stable, adjustable reference voltage.

[0013] Figs. 1-4 show examples of application of the invention. Figs. 1, 2 show the experimental reverse branches of the current-voltage characteristics of a photodiode when illuminated by a white SMD LED (Fig. 1) and a transistor optocoupler (Fig. 2). The signatures to the curves indicate the voltages on the SMD LED and the emitter of the transistor optocoupler. It follows from the measurement results that it is possible to change the stabilization current within a few milliamps. Fig. 3 shows the basic electrical circuit of a full-wave rectifier with a photodiode as a zener diode. An alternating sinusoidal signal with an RMS voltage of 15 V and a frequency of 1 kHz is applied to the input of the circuit. A stable direct voltage of -1.16 V is obtained at the output of the circuit. Fig. 4 shows the oscillograms of the signals in all nodes of the circuit.

Claims

1. A method for stabilizing voltage in electrical circuits, which includes the use of a pn-junction of an optoelectronic device in reverse connection, the effect of electromagnetic radiation of the optical range on the photodiode crystal, the absorption of electromagnetic radiation by the pn-junction of the photodiode crystal, the creation in the region of the pn-junction of an electric field with a voltage equal to the breakdown voltage, depending on the intensity of the optical radiation, and the regulation of current and voltage is carried out using optical radiation.

2. A method for stabilizing voltage in electrical circuits, which includes the use of a pn-junction of an optoelectronic device in reverse connection, the effect of electromagnetic radiation of the optical range on the crystal of a phototransistor, the absorption of electromagnetic radiation by the pn-junction of the crystal of the phototransistor, the creation in the region of the pn-junction of an electric field with a voltage equal to the breakdown voltage, depending on the intensity of the effect of optical radiation, and the regulation of current and voltage is carried out using optical radiation.

3. A method for stabilizing voltage in electrical circuits, which includes the use of a pn-junction of an optoelectronic device with reverse connection, the effect of electromagnetic radiation of the optical range on the crystal of a photothyristor, the absorption of electromagnetic radiation by the pn-junction of the crystal of the photothyristor, the creation in the region of the pn-junction of an electric field with a voltage equal to the breakdown voltage, depending on the intensity of the effect of optical radiation, and the regulation of current and voltage is carried out using optical radiation.

4. A method for stabilizing voltage in electrical circuits, which includes the use of a pn-junction of an optoelectronic device with reverse connection, the effect of electromagnetic radiation of the optical range on the crystal of a photodetector of a diode optocoupler, the absorption of electromagnetic radiation by the pn-junction of the crystal of the photodetector, the creation in the region of the pn-junction of an electric field with a voltage equal to the breakdown voltage, depending on the intensity of the effect of optical radiation, and the regulation of current and voltage is carried out using optical radiation.

5. A method for stabilizing voltage in electrical circuits, which includes the use of a pn-junction of an optoelectronic device with reverse connection, the effect of electromagnetic radiation of the optical range on the crystal of a photodetector of a transistor optocoupler, the absorption of electromagnetic radiation by the pn-junction of the crystal of the photodetector, the creation in the region of the pn-junction of an electric field with a voltage equal to the breakdown voltage, depending on the intensity of the effect of optical radiation, and the regulation of current and voltage is carried out using optical radiation.

6. A method for stabilizing voltage in electrical circuits, which includes the use of a pn-junction of an optoelectronic device with reverse connection, the effect of electromagnetic radiation of the optical range on the crystal of a photodetector of a thyristor optocoupler, the absorption of electromagnetic radiation by the pn-junction of the crystal of the photodetector, the creation in the region of the pn-junction of an electric field with a voltage equal to the breakdown voltage, depending on the intensity of the effect of optical radiation, and the regulation of current and voltage is carried out using optical radiation.

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