346 results about "Zener diode" patented technology

A transient voltage surge protection circuit includes a discharge transistor having a drain coupled to a first point of a voltage input bus, and a source coupled to ground; an RC string having a first capacitor and a first resistor coupled in series; a first charge transistor having a drain coupled to the drain of the discharge transistor, a source coupled to the gate of the discharge transistor, and a gate coupled to a mid-point between the first capacitor and the first resistor; a second charge transistor having a drain coupled to the drain of the discharge transistor and a gate coupled to the gate of the first charge transistor; a Zener diode string coupled to a second point of the voltage input bus and coupled to a third and fourth resistors in series. A midpoint between the third and fourth resistors is coupled to the second resistor.

The invention discloses an active power synthesis network of a micro-strip and waveguide hybrid architecture. The active power synthesis network comprises a micro-strip power division network, a micro-strip power amplification circuit, a waveguide power combiner and a power-on / power-off sequence control circuit. The power synthesis network is designed by adopting a micro-strip and waveguide hybrid architecture, so that the overall size can be greatly reduced on the premise of ensuring the power capacity of the power synthesis network; the power-on / power-off sequence control circuit based on the Zener diode is designed, the power amplification chip can be effectively protected and prevented from being damaged due to the wrong power-on / power-off sequence, meanwhile, the number of power needing to be supplied to the power amplification chip at the same time is reduced, and the use complexity of the power synthesis module is reduced.

The utility model discloses an intrinsic safety power supply circuit and a fuel electrochemical oxygen analyzer. The intrinsic safety power supply circuit comprises a first MOS tube, a first capacitor, a second capacitor, a first resistor, a first Schottky diode, a first Zener diode and a second Zener diode, the power supply module of the fuel electrochemical oxygen analyzer comprises the intrinsic safety power supply circuit and further comprises a sensor module, an AD conversion module, a key module, a single chip microcomputer module, an analog output module and a display driving module which are connected with the power supply module, and the single chip microcomputer module is connected with the AD conversion module, the key module, the analog output module and the display driving module. The sensor module is connected with the AD conversion module, and the analog output module is connected with external equipment; the fuel electrochemical oxygen analyzer adopts the intrinsically safe power supply circuit to limit the working current and voltage in the circuit so as to control the power consumption of the whole machine, so that explosion prevention is realized, and the fuel electrochemical oxygen analyzer can measure the oxygen concentration in a flammable and explosive environment.

The utility model relates to the technical field of electronic circuits, and discloses a protection circuit and communication equipment, and the protection circuit comprises a transmission module and a control module. The input end of the transmission module is used for receiving an electric signal, and the transmission module is used for transmitting the electric signal from the input end to the output end in a conducting state; the control module comprises a control unit and a switch unit; the control unit comprises a voltage stabilizing tube; the anode of the voltage-regulator tube is connected with the first end of the switch unit, the cathode of the voltage-regulator tube is connected with the output end of the transmission module, the second end of the switch unit is connected with the control end of the transmission module and a voltage source, and the third end of the switch unit is grounded; when the voltage-regulator tube is reversely broken down, the switch unit is switched to the conducting state, and the transmission module is switched to the cut-off state from the conducting state. The protection circuit can effectively protect the communication chip when abnormal high voltage occurs.

The invention discloses a split gate field effect transistor with an ESD discharge path and a low-cost preparation method thereof. The split gate field effect transistor comprises a low-resistance N + substrate, two ends of the low-resistance N + substrate are respectively provided with a drain metal and an epitaxial layer, the top of the epitaxial layer is provided with a plurality of grooves, the side walls of the grooves are covered with first dielectric layers, and split gates and control gates are arranged in the grooves; the control gate and the split gate are isolated through a second dielectric layer in the range of the active region, the control gate and the split gate are short-circuited in the range of the transition region, the short-circuited part of the control gate is provided with a plurality of P-type regions, and the plurality of P-type regions are connected through N-type regions. According to the split gate field effect transistor, a plurality of PN junctions are introduced between the control gate and the split gate of the transition region of the traditional split gate field effect transistor to form a back-to-back Zener diode, and when an ESD event occurs, electrostatic charges are discharged through the Zener diode, so that the voltage between the gate and the source is not higher than the rated gate-source voltage, and the gate and the source are prevented from breaking down and damaging the device.

The invention belongs to the technical field of integrated circuits, and particularly relates to a high-voltage LDO (Low Dropout Regulator) circuit with an off-chip capacitor, which comprises an error amplifier EA, a buffer circuit BUFFER, a power tube made of a first P-type DEMOS, an output voltage dividing sampling resistance circuit consisting of a first resistor R1 and a second resistor R2, a floating rail circuit, an enabling circuit and a load capacitor, the floating rail circuit comprises a Zener diode and a third resistor, and a floating low power rail VFLOAT having a stable difference value with the input voltage is provided for the EA and the BUFFER through the reverse bias breakdown voltage of the Zener diode; according to the characteristics of low output impedance and low input parasitic capacitance of the BUFFER circuit, a low-frequency secondary pole composed of an EA high output resistor and a power tube large grid parasitic capacitor is split into two high-frequency poles, and the loop stability of the high-voltage LDO is guaranteed.

The utility model discloses a power supply module and an SoC chip, and belongs to the field of circuits. The power supply module provided by the utility model comprises a voltage stabilizing diode, a first RC circuit and a first power supply chip, the first power supply chip is provided with an input pin, an enabling pin and an output pin; an input pin of the first power supply chip is connected with the power supply end, an enabling pin of the first power supply chip is connected with the power supply end through the first RC circuit and the voltage stabilizing diode in sequence, and an output pin of the first power supply chip is coupled with the first voltage output end; wherein the positive electrode of the voltage stabilizing diode is connected with the first RC circuit, and the negative electrode of the voltage stabilizing diode is connected with the power supply end.

A power supply circuit of an embodiment includes a first transistor including a source connected to an input terminal, and a gate connected to a first node; a second transistor including a drain connected to a drain of the first transistor, and a source connected to an output terminal; a third transistor including a source connected to the input terminal, a drain connected to the first node, and a gate connected to a second node; and a Zener diode including an anode connected to the input terminal, and a cathode connected to the second node.

A voltage tester system / device for safety application in AC & DC electrical systems and method thereof. The system / device includes a voltage presence indicator (VPI) circuit including plurality of zener diodes, bi-directional current-limiter circuits, VPI-LEDs and an absence of voltage tester (AVT) circuit including plurality of comparator circuits, optocouplers, DC-DC converters, microcontroller, power-management circuit, battery, LEDs and diodes. The VPI circuit converts electrical energy potential between the lines in range of 3 to 3394 volts (phase to neutral) / 5.2 to 5879 volts (phase to phase) into electrical inputs that drives VPI-LEDs to produce light output. The AVT circuit helps in checking circuit wires intactness with their respective busbars and verify absence of hazardous voltage by providing positive indication with a GREEN-light when safe voltage level is attained at connected leads, and voltage is less than a preset threshold value.

A semiconductor device includes a body, a first electrode, and an insulation layer. The body includes: a first semiconductor region of a first conductive type; a second semiconductor region of a second conductive type formed at a position where the second semiconductor region is in contact with the first electrode and the insulation layer; and a third semiconductor region of the first conductive type formed in contact with the second semiconductor region such that the third semiconductor region surrounds the second semiconductor region as viewed in a plan view. In the semiconductor device, assuming a total amount of dopants in the second semiconductor region as S1 and a total amount of dopants in the third semiconductor region as S2, a relationship of S1<S2 is satisfied, and a combination of the second semiconductor region and the third semiconductor region has a function of a Zener diode.

A switching converter comprises an input terminal for receiving an input voltage, an output terminal for providing an output voltage, an input switching circuit, an energy storage circuit having a capacitor, and a pre-charge circuit. The input switching circuit has a first switch and a second switch coupled in series to form a switch node. The energy storage circuit has a capacitor coupled to the switch node. The pre-charge circuit is coupled between the input terminal and the switch node, having a Zener diode and a resistor coupled in series. A cathode of the Zener diode is coupled to the input terminal. The pre-charge circuit charges the capacitor during startup of the switching converter and stops charging the capacitor based on the input voltage.

The present application provides a kind of driving device, prevent the overcurrent detection input terminal voltage due to the current flowing in the chip peripheral ground wiring rises and thus generates the false operation of overcurrent detection circuit.In the IS terminal of overcurrent detection circuit arranged in the position far away from GND terminal and the B point of chip peripheral ground wiring (11) are provided as terminal protection circuit transistor MN1, in the CFO terminal arranged in the position further away from GND terminal and the C point of chip peripheral ground wiring (11) are provided as terminal protection circuit zener diode ZD1.In addition, the input of the acceptance threshold voltage of comparator COMP_IS and the B point of chip peripheral ground wiring (11) are provided as potential offset element transistor MN2.Between thus, when the potential of B point rises due to the overvoltage applied to CFO terminal, by making the two input terminals of comparator COMP_IS also rise, thereby preventing false operation.

The utility model relates to a low-cost protection circuit which comprises an input circuit, the output end of the input circuit is electrically connected with the power supply ends of a first control circuit, a second control circuit and an output control circuit at the same time, and the output end of the first control circuit is electrically connected with the grounding ends of the second control circuit and the output control circuit at the same time. The output end of the second control circuit is electrically connected with the control end of the output control circuit, and the input circuit, the first control circuit, the second control circuit and the output control circuit are all composed of discrete components. According to the scheme, the low-cost protection circuit is only composed of the two MOS tubes, the two voltage stabilizing diodes, the triode, the resistor, the capacitor and the switch, has the advantages of being simple in circuit and low in cost, and can achieve multiple protection functions of power supply overvoltage, undervoltage, reverse connection and surge current impact at the same time. The performance is reliable, an IC or an optocoupler or a single-chip microcomputer chip does not need to be arranged, programming codes are not needed, production is convenient, and the production efficiency is improved.

To suppress malfunction of an upper arm power semiconductor element even when disturbance noise occurs.SOLUTION: A power conversion device 11 includes: an upper arm IGBT 13 provided between a main DC power source Vdc and an output-terminal Pout; a gate short-circuit MOSFET 17 provided between a first gate terminal 13G related to the upper arm IGBT 13 and the output terminal Pout and in which a first parasitic capacitance Cgs is provided in parallel; a first zener diode DZ1 provided between a second gate terminal 17G related to the gate-short-circuit MOSFET 17 and the output-terminal Pout; a first diode D1 provided between the main DC power source Vdc and the first zener diode DZ1 and in which a second parasitic capacitance Cd1 is provided in parallel; and a second diode D2 provided close to the first diode D1 and configured to irradiate the first diode D1 with light.SELECTED DRAWING: Figure 3

The utility model discloses a dual-optocoupler protection circuit, which comprises a chip U1, an optocoupler U2 and an optocoupler U3, and is characterized in that the FB end of the chip U1 is connected with the fourth pin of the optocoupler U2 and the fourth pin of the optocoupler U3; a pin 3 of the optocoupler U2 is connected with a pin 3 of the optocoupler U3; a pin 2 of the optocoupler U2 is connected with a pin 1 of the optocoupler U3; a pin 1 of the optocoupler U2 is connected with a resistor R121 and a resistor R98, the resistor R121 is connected with a voltage stabilizing diode ZD6, and the voltage stabilizing diode ZD6 is connected with a resistor R120; and the resistor R98 is connected with the pin 2 of the optocoupler U2 and the pin 1 of the optocoupler U3. According to the utility model, the damage of the power supply caused by failure of a single device can be met, the power supply and the personal safety of a user can be better protected, and the protection circuit can be better applied to the market due to more and more safety accidents caused by failure of a charger and higher and higher requirements on the safety of the charger at present.

The invention relates to a driver circuit for one or more power semiconductors (SD), the driver circuit comprising: at least one first switch (S1) and at least one second switch (S2), the driver circuit being connectable both to the lower switching potential and to the upper switching potential, a connection to the lower switching potential or to the upper switching potential being enabled by operation of the at least one first switch (S1) and of the at least one second switch (S2); a capacitor (Ctr) and a Zener diode (D0), the capacitor (Ctr) and the Zener diode (D0) being arranged in parallel branches, the parallel branches being connected on a first side to the connection of the switches (S1, S2), and the parallel branches being connected on a second side to the gate terminal of the power semiconductor (SD) to be driven, characterised in that the branch including the capacitor (Ctr) also comprises a resistor (RGon), and wherein in addition a protection circuit (OPT) comprising a further Zener diode and an antiserially connected diode is provided between the gate terminal (G) of the power semiconductor (SD) to be driven and the source terminal (S) of the power semiconductor (SD) to be driven.

The utility model particularly relates to an active LED afterglow removing circuit, which comprises a VIN end, a grounding end GND, a light emitting diode LED1, a first field effect transistor Q1, a second field effect transistor Q2 and an ON / OFF control end, and is characterized in that the VIN end is connected to one end of a third resistor R3; the cathode of the LED 1 is connected with the pin 3 of the second field effect transistor Q2; a pin 1 of the second field effect transistor Q2 is connected to a pin 2 of the first field effect transistor Q1; a pin 3 of the first field effect transistor Q1 is connected with a grounding end GND; the first pin of the first field effect transistor Q1 is connected with an ON / OFF control end, a first capacitor C1 and a voltage stabilizing diode Z1 are connected between the first pin and the third pin of the second field effect transistor Q2 in parallel, the afterglow phenomenon is thoroughly eliminated through an active discharge mechanism, and the problems that a traditional passive scheme is delayed in response and high in cost are solved. The circuit is simple in structure and high in compatibility, and has the advantages of low cost and high reliability.

The invention relates to an illumination device for illuminating a space exposed to ionising radiation, the device comprising: a power supply circuit having an input for receiving alternating current from a mains electricity grid and an output suitable for delivering a direct current in response to receiving the alternating current, the power supply circuit comprising a diode bridge, and an illumination circuit (50) connected to the output of the power supply circuit, the illumination circuit comprising: a plurality of light-emitting diodes (51) connected in series, a plurality of Zener diodes (52), each connected in parallel with one or more light-emitting diodes of the plurality of light-emitting diodes and at least one resistor (53) connected in series with the plurality of light-emitting diodes, wherein a cumulative nominal supply voltage of the plurality of light-emitting diodes connected in series is adapted to a nominal voltage of the mains electricity grid.

The application discloses a current monitoring circuit and a monitoring method. The current monitoring circuit comprises a Zener diode, an operational amplifier, a first MOSFET, a second MOSFET and a current mirror circuit. The current monitoring circuit and the monitoring method do not need to use a single-chip integrated or customized power tube, and accurately provide a current proportional to a current flowing through a required monitoring power switch for system monitoring.

This invention provides a high-voltage suppression and voltage regulation protection circuit, relating to the field of circuit protection technology. The circuit includes a high-voltage discharge elimination circuit, a π-type composite EMI filter network circuit, and a voltage regulator circuit connected in sequence, with terminals at both the input and output ends. The high-voltage discharge elimination circuit consists of four DC spark discharge tubes and two varistors. The π-type composite EMI filter network circuit includes two high-voltage ceramic capacitors, two inductors, and one common-mode inductor. The voltage regulator circuit consists of an electrolytic capacitor and a Zener diode. Through the synergistic effect of the front-stage high-voltage elimination, intermediate-stage filtering, and rear-stage voltage regulation, the circuit achieves suppression and voltage regulation protection against high-voltage interference ranging from kilovolts to tens of kilovolts, ensuring continuous normal operation of the circuit system under harsh high-voltage environments.

This invention discloses a primary-side feedback output no-load voltage stabilization circuit, including a transformer T1. One end of the N1 coil of the transformer T1 is connected to the voltage feedback pin of the main control unit U1, and the other end is grounded. One end of the N2 coil of the transformer T1 is connected to the collector of the transistor Q2 through a diode D2, and the VCC voltage output from the emitter is supplied to the VDD terminal of the main control unit U2. The cathode of the diode D2 is grounded through a capacitor EC1, and the cathode is also connected to the voltage terminal through resistors R9 and R10 respectively. The cathode of the diode D2 is also connected to the base of the transistor Q2 through a resistor R11, and the base is also grounded through a Zener diode ZD1.

A reliability test method and test circuit for a voltage stabilizing diode array, belonging to the field of semiconductor voltage stabilizing diode testing. It includes: using a constant current tube to provide a power aging current to the voltage stabilizing diode array to be tested, while monitoring and protecting the voltage stabilizing diode array to be tested; using a light-emitting diode and a voltage stabilizing diode to form a short-circuit indication circuit to feedback the short-circuit problem of the aging product; using a light-emitting diode and a constant current tube to form an aging indication circuit, protecting the normal operation of the light-emitting diode through the constant current tube, and at the same time used for product open-circuit indication; using a shunt circuit to limit the current of the aging path to protect the voltage stabilizing diode array to be tested and other components; using a DIP switch to specify the circuit aging of a certain path of the voltage stabilizing diode array to be tested; connecting an ammeter in series at one end of the DIP switch to achieve single-path current monitoring. It solves the problems of large current fluctuation in the existing semiconductor voltage stabilizing diode aging circuit and no protection measures in the circuit. It is widely used in the power aging of semiconductor voltage stabilizing diode series products.

A Zener diode includes a P + anode, a polysilicon mesh ring on a surface of a semiconductor substrate and surrounding the P + anode, an N + cathode opposite the P + anode with respect to the polysilicon mesh ring, an outer spacer on an outer portion of the polysilicon mesh ring adjacent the N + cathode, and an inner spacer located on an inner portion of the polysilicon mesh ring adjacent to the P + anode. The polysilicon mesh ring may be a polysilicon layer on a TEOS layer. The Zener diode may be located in a lightly doped N-well, wherein a Zener junction includes an N-well high region adjacent to and below the P + anode. The Zener diode may be located in a highly doped N-well, where the Zener junction includes a P-structure formed in the highly doped N-well in an upper portion of the semiconductor substrate and adjacent to and surrounding the P + anode.

This application relates to the field of analog integrated circuit technology and discloses a voltage reference circuit suitable for high power supply voltages. The circuit replaces the Zener diode pre-regulation architecture with a voltage-limiting loop biased by a positive temperature coefficient current source. A stable low power supply voltage is generated by forming a negative feedback loop through a high-voltage regulating transistor and a feedback sampling transistor. A reference voltage is generated by subtracting the gate-source voltages of two sets of transistors with different threshold voltages. Furthermore, it incorporates a frequency-band coordinated power supply rejection ratio enhancement module, a pre-charging and automatic loop exit startup acceleration module, and a dual-branch complementary control trimming module. This circuit achieves a comprehensive performance of small area, low power consumption, high power supply rejection ratio, and fast startup.

The utility model relates to the technical field of bending machines, in particular to a voltage stabilizing diode bending machine which comprises a base, a placing table, a pressing plate, an ejector rod, a bending block and a driving rod. The base provides installation conditions for other mechanisms, a Zener diode containing groove is formed in the containing table, when a Zener diode is placed in the containing groove, the distance between the bending positions of pins at the two ends and the end face position of the Zener diode is consistent, and when the pins of the Zener diode are bent, a worker places the Zener diode on the containing table with the hands, and the bending efficiency is improved. The pressing plate is placed on the top of the placing table to press the Zener diode, at the moment, the driving piece is started through the controller, and the driving piece operates to push the bending block to ascend, so that the bending block is matched with the ejector rod to bend two pins of the Zener diode at the same time, and then it is guaranteed that the distance between the bending position of the pins of the Zener diode and the end face position of the Zener diode is consistent; the problem that the distances between the bending angles of two pins and the end face of a diode are inconsistent due to the fact that an existing bending device cannot ensure bending at the same point position is solved.

This utility model discloses a high-voltage protection control circuit, including a first connector CN1 and a second connector CN2. Between the first connector CN1 and the second connector CN2, there are also: a second Zener diode D2, a first Zener diode D1, a second transistor Q2, a first transistor Q1, a switching transistor Q3, a voltage divider resistor R8, and a step-down chip U1. This utility model utilizes the second Zener diode D2 and the first Zener diode D1 to implement the avalanche effect, directly driving the second transistor Q2 and the first transistor Q1, and delaying overvoltage response, resulting in a significant improvement in response speed. Furthermore, the combination of the second Zener diode D2, the first Zener diode D1, the second transistor Q2, the first transistor Q1, and the switching transistor Q3 implements a complete protection function, reducing the overall circuit area and achieving high circuit integration. Moreover, it eliminates the need for a dedicated IC chip for control, reducing production costs.

The utility model discloses a high-efficiency linear direct-current power supply with a transformer secondary tap capable of zero-crossing automatic switching, which is characterized in that a 220V power supply is subjected to voltage reduction through a transformer T, terminals 4, 3, 2 and 1 of the transformer respectively output different alternating-current voltages, the terminals 4 and 1 are connected with the input end of a bridge rectifier B, the terminals 3 and 2 are respectively connected with a working ground through backward diodes D6 and D5, and the working ground is connected with the working ground through the reverse diodes D6 and D5. A transistor T1, resistors R1, R2, R3 and R4, a potentiometer P1 and a voltage stabilizing diode D7 form a grid trigger circuit of a one-way silicon controlled rectifier Th1, when small and medium loads are loaded, reverse breakdown of the D7 is just achieved by adjusting the voltage of the P1 and the sliding end, T1 is conducted, the silicon controlled rectifier Th1 is cut off, and a terminal 4-2 or a terminal 1-3 of a transformer T supplies power to the loads; when the load is heavy, the Uo drops, the result is that the sliding end voltage of the P1 cannot enable the D7 to be reversely broken down, the D7 is cut off, the T1 is cut off, the Th1 is conducted, and the transformer terminal 4-1 or 1-4 provides a power supply for the load.

The utility model relates to the technical field of light-emitting semiconductors, and particularly discloses a vertical LED light-emitting device, which comprises a metal substrate, a light-emitting diode, a Zener diode, a first bonding wire, a second bonding wire and a packaging adhesive layer, the light-emitting diode is fixed above the metal substrate, the Zener diode is fixed on one side of the upper surface of the light-emitting diode, one end of the first bonding wire is connected with an electrode at one end of the metal substrate, the other end of the first bonding wire is connected with the light-emitting diode, and the other end of the first bonding wire is connected with the metal substrate. One end of the second bonding wire is connected with an electrode at the other end of the metal substrate, and the other end of the second bonding wire is connected with the Zener diode; and the packaging adhesive layer covers the metal substrate, the light emitting diode, the Zener diode, the first bonding wire and the second bonding wire. According to the utility model, through the design that the Zener diode is connected with the light emitting diode in parallel, an extra electrostatic protection mechanism is provided for the LED.

This application provides a multiplier circuit with small area and low temperature drift. The multiplier circuit includes a first voltage module for receiving a first input current I1 and a second input current I2, and generating a first control voltage related to the first input current I1 and the second input current I2; a current module including a first resistor R1 and a first Zener diode D1 for generating a reference current IM1 in the circuit, the reference current IM1 being related to the first Zener diode D1 and the first resistor R1; a second voltage module connected to the first voltage module and the current module for generating a second control voltage related to the reference current IM1 and the output current IM2 driven by it, the second control voltage and the first control voltage satisfying a specific formula; and an output module including a second resistor R2 for converting the output current IM2 into an output voltage V. O And make the output voltage V O It satisfies a specific formula.

The utility model discloses a charging circuit capable of automatically switching between an intelligent POS machine base and USB charging. The circuit structurally comprises a charging chip U15, a charging chip U16, an MOS parasitic diode Q4, an MOS parasitic diode Q5, a triode Q6A, a triode Q6B, a triode Q7A, a triode Q7B, a bidirectional voltage stabilizing diode D14, a bidirectional voltage stabilizing diode D15, a capacitor C83, a capacitor C84, a capacitor C85, a resistor R84, a resistor R85, a resistor R86, a resistor R87, a resistor R88, a resistor R89, a resistor R90, a resistor R91, a resistor R92, a resistor R93, a resistor R94, a resistor R95, a resistor R161, a resistor R162, a resistor R163 and a resistor R166. Source electrodes of the Q4 and the Q5 are connected together to form a selection node, grid electrodes of the Q4 and the Q5 are controlled by the Q6A and the Q6B respectively, and either USB power supply or base power supply is achieved. The nEN end of the U15 is connected with DOCKVCC through the R92, when the base is inserted, the U15 is automatically closed, the base is preferentially used for power supply, and circulation is prevented; according to the circuit, the MOS parasitic diode characteristic is utilized, a conduction path is automatically switched when only a USB, only a base or double power supplies coexist, and stable charging of the POS machine is ensured.