54results about How to "Avoid simultaneous conduction" patented technology

The invention discloses a motor drive circuit with dead band time delay. The motor drive circuit comprises an H-bridge circuit connected with a motor. The H-bridge circuit is controlled by a photoelectric isolating circuit, a dead band time delay control circuit and a half-bridge drive control circuit and controls the steering of the motor through adjusting breakover and the check time order of an MOS tube. A pair of complementary input signals are output through a double-path photoelectric coupler, and two paths of signals enter the dead band time delay control circuit. Control signals complementary with two alternative denial gate output paths are in concatenation through two paths. Signals output by the dead band time delay control circuit are respectively input to two symmetric units in the half-bridge drive control circuit. The dead band delay control circuit controls the time of a dead band, and simultaneous breakover of two MOS tubes of the same arm is prevented. Dead band time can be adjusted flexibly. The photoelectric isolating circuit increases anti-interference capacity, and reduces interference of H-bridge control signals to a front-grade circuit when an H-bridge outputs large currents in an instant state or a motor is started. The motor drive circuit can work with power supplied by a single power supply.

An IGBT device, comprising a substrate having a conductivity type; a drain electrode arranged on a bottom surface of the substrate; an epitaxial layer arranged on the substrate and having a conductivity type opposite that of the substrate; at least one body diffusion arranged within the epitaxial layer and having a conductivity type the same as that of the substrate; at least one source diffusion arranged within the body diffusion and having a conductivity type the same as that of the epitaxial layer; a gate electrode to control the IGBT device; a source electrode electrically coupled to the body diffusion and the source diffusion; an additional diffusion arranged within the epitaxial layer and having a conductivity type the same as that of the substrate, the additional diffusion forming a collector region of a vertical bipolar arrangement in the IGBT; and a sense electrode electrically coupled to the additional diffusion; wherein the presence of minority carriers in the epitaxial layer may be detected in accordance with a voltage of the sense electrode.

A switching power supply unit of the present invention includes a timing generating circuit (121) which receives a first control signal formed by a rectifier-transistor driving circuit (104), forms a second control signal based on the first control signal, and supplies the second control signal to a control electrode of the rectifier transistor (113). The first control signal is synchronized with the switching operation of a half-bridge circuit (102), and the second control signal exceeds a threshold voltage of a rectifier transistor (113) at a timing substantially equal to the timing that one edge of the first control signal is generated and falls below the threshold voltage of the rectifier transistor (113) at a timing earlier by predetermined time than the timing that the other edge of the first control signal is generated.

The invention relates to a battery balanced charging controller and a battery module thereof. The battery balance charging controller comprises a voltage division device, a switch module and a balanced circuit, wherein the voltage division device is coupled between a first end and a second end of a battery and provides an upper reference potential and a lower reference potential, and the upper reference potential is higher than the lower reference potential; the switch module comprises a first switch and a second switch; the balanced circuit is coupled with a connecting point, the voltage division device and the switch module and determines whether balanced charging current flows through the first switch or the second switch or not according to the potential of the connecting point, the upper reference potential and the lower reference potential, which battery unit has insufficient voltage in the battery module is judged by utilizing the reference voltage provided by the voltage division device, and the balanced circuit is adopted to control the switch module so that the charging current of the battery unit with lower voltage is higher than that of a battery unit with higher voltage, thereby the voltages of all batteries can be ensured to be consistent while in fully charging. The battery module comprises battery units with the number of N+1and battery balanced charging controllers with the number of N, can be applied to battery balanced charging controllers and has wider application scope.

A DC converter comprises a half bridge supply circuit and one or more flyback or forward converter output circuits, and optionally also an LLC converter whose control can determine a common variable switching frequency. The half bridge supply circuit produces a 50% duty output alternating between two input voltages, such as zero and a voltage Vin. In each flyback or forward converter output circuit, a switch connects a transformer primary to the half bridge supply circuit output in a PWM controlled manner to regulate a respective flyback or forward converter DC output which is produced by the converter output circuit, with a duty ratio less than 50% whereby switching losses are reduced. Soft switching is further facilitated by the half bridge supply circuit having two transistors controlled in a complementary manner.

The invention relates to a repelling drive circuit for an H bridge of a motor. The repelling drive circuit comprises drive circuits which are connected with four bridge arms of an H bridge circuit respectively, wherein each bridge arm drive circuit comprises an isolating photocoupler for carrying out photoelectric isolation, and a repelling photocoupler for carrying out repelling on the bridge arm drive circuits at the same side of the H bridge; the repelling photocouplers on the same bridge arm are connected with primary sides of the isolating photocouplers in series; and secondary sides of the repelling photocouplers are connected with the primary sides of the isolating photocouplers on different bridge arms at the same side, so that the repelling photocouplers are simultaneously conducted when signals of the isolating photocouplers at the same side of the H bridge are controlled to be simultaneously effective. The secondary sides of the repelling photocouplers are connected with the primary sides of the isolating photocouplers on different bridge arms at the same side and the signals form a passage through the secondary sides of the repelling photocouplers, so that the isolating photocouplers are cut off; and switch tubes of the upper bridge arm and the lower bridge arm at the same side of the H bridge are free of a drive signal to achieve the target of drive repelling of the motor.

The invention discloses a self-oscillation DC-DC circuit. The source electrode of a switch MOS tube M1 is connected with a DC power supply Vin, the drain electrode of the switch MOS tube M1 and the drain electrode of a switch MOS tube M2 are connected with one end of an energy storing inductor L1, the grid electrode of the switch MOS tube M1 and the grid electrode of the switch MOS tube M2 are connected to two output ends of a switch driver respectively, the source electrode of the switch MOS tube M2 is connected to the ground, the other end of the energy storing inductor L1 is connected with the anode of an energy storing capacitor C1 and a load, the cathode of the energy storing capacitor C1 is connected to the ground, the two input ends of a triangular wave generation circuit are connected to the two ends of the energy storing inductor L1 in parallel, the output end of the triangular wave generation circuit is connected with the source signal input end of a comparison circuit, two window signal input ends of the comparison circuit are connected to the window voltage, and the output end of the comparison circuit is connected with the input end of the switch driver. The self-oscillation DC-DC circuit is characterized by simple structure, self oscillation, free of an amplification circuit, rapid response, low power consumption, low electromagnetic interference and the like.

In a self-excited generator 1 including an automatic voltage regulator (AVR) 10, a condensive load protection device includes: a field current control driver 21 which is connected to the field winding 6 in series and controlled to be ON / OFF by a drive circuit 23 of the AVR 10 to supply a field current to the field winding 6; and a condensive load protecting rotor short-circuit driver 22 which is connected in parallel to the field winding 6, and supplies a short-circuit current to the field winding 6 by being turned ON, and a bootstrap circuit 30 is connected as a drive power supply of the field current control driver and the condensive load protecting rotor short-circuit driver, and the bootstrap circuit 30 includes a capacitance portion 32 in which charges are accumulated when the field current control driver 21 is ON.

The invention discloses a simple pulse switch power supply PWM generation circuit and method. The PWM generation circuit comprises a resonance module, a dead zone time setting module and a shaping reverse module. The dead zone time setting module is electrically connected between the resonance module and the shaping reverse module. The resonance module is subjected to self-excited oscillation to generate square signals. After the square signals pass through the dead zone time setting module and the shaping reverse module in sequence, a first PWM pulse signal and a second PWM pulse signal which are used for driving bridge-wall-different MOS transistors of a pulse switch power supply respectively are obtained, the first PWM pulse signal and the second PWM pulse signal being the same in duty ratio and having set dead zones. The circuit is simple and high in cost performance; the circuit is in complete hardware implementation; the whole processing process does not need the intervention of control circuits such as CPU and the like; the circuit is high in reliability and effectively helps to solve the defects that in the prior arts, the size a chip is big and the number of pins is large; and the peripheral circuit of the circuit only has resonance module and the dead zone time setting module, so that the size of the pulse switch power supply is allowed to be minimized.

The invention discloses a method for driving a switching tube of a power unit board, which comprises the following steps of: respectively receiving a pulse width modulation signal from a master control board and a dead time value signal corresponding to the pulse width modulation signal; after the dead time value signal is analyzed, obtaining a dead time value; analyzing a dead time value signal to obtain a dead time value; comparing the dead time value obtained after the dead time value signal is analyzed with a preset numerical value; if the dead time value obtained by analyzing the dead time value signal is less than the preset numerical value, determining the preset numerical value as the dead time value to be loaded into the pulse width modulation signal; loading the determined dead time value to be loaded into the pulse width modulation signal into the pulse width modulation signal to generate a new pulse width modulation signal; and according to the new pulse width modulation signal, driving switching tubes in the power unit board. According to the method for driving the switching tube of the power unit board, which is disclosed by the invention, the upper switching tube and the lower switching tube are prevented from being simultaneously conducted.

The invention discloses an abnormal protection circuit for an intelligent power module. The abnormal protection circuit comprises a first P-channel metal oxide semiconductor (PMOS) transistor 301, a first N-channel metal oxide semiconductor (NMOS) transistor 302, a lower bridge arm power supply 303, a first insulated gate bipolar transistor (IGBT) 304, a second PMOS transistor 305, a second NMOS transistor 306, an upper bridge arm power supply 307 and a second IGBT 308. A lower bridge arm driving signal LIN is connected with a gate of the first PMOS transistor 301, the gate of the first NMOS transistor 302 and an input end of the first abnormal protection circuit 309. A drain of the first PMOS transistor 301 is connected with the drain of the first NMOS transistor 302, and is also connected with the gate of the first IGBT 304 and the first and second output ends of the first abnormal protection circuit 309, and the point of the later connection is marked as LO. The abnormal protection circuit can timely discover the abnormality an IGBT gate connecting line and timely switch the IGBT off, and has the characteristics of simple and rational structure, operational flexibility, high degree of safety and wide application range.