Abstract: A lossless exciting current sampling circuit for an isolated converter includes first and second voltage sampling circuits and a subtraction circuit formed by an operational amplifier. The two sampling circuits sample voltages of the primary winding of an isolation transformer, with outputs fed into the subtracter. The subtracter output is the circuit's output. RC low-pass filters with large time constants are used as primary voltage sampling circuits, realizing integration of voltage differences between the exciting inductance terminals, enabling lossless current sampling without resistors or transformers. The current sampling result is utilized for volt-second balance control, realized along with a hold circuit and comparator which compares the sampling hold result with the current sampling result to generate a control signal.

Abstract: A power semiconductor device includes: a substrate; drain metal; a drift region; a base region; a gate structure; a first conductive type doped region contacting the base region on the side of the base region distant from the gate structure; a source region provided in the base region and between the first conductive type doped region and the gate structure; contact metal that is provided on the first conductive type doped region and forms a contact barrier having rectifying characteristics together with the first conductive type doped region below; and source metal wrapping the contact metal and contacting the source region.

Abstract: The present invention discloses an ultralow-power negative margin timing monitoring method of a neural network circuit, relates to an adaptive voltage regulation technology based on on-chip timing detection, and belongs to the technical field of low-power design of integrated circuit. The present invention provides an ultralow-power operating method of neural network circuit. By inserting a timing monitoring unit in specific position of critical paths and setting partial circuits to operate under “negative margin”, the system can further lower voltage, compress the timing slack, and obtain higher power gain.

Abstract: An adaptive load optimization method for a resonant gate drive circuit is provided to optimize the switching loss, turn-on loss and gate drive loss under different MOSFET loads. A data table is pre-stored in a digital signal processor chip (DSP), and voltages and pre-charge times, corresponding to a low total loss, of the resonant gate driver obtained by actual tests in case of different load currents are recorded in the data table; and in actual application, after an analog-to-digital converter terminal (ADC) samples a load current, a load current, closest to the sampled load current, is read from the data table, and the digital signal processor chip (DSP) is enabled to perform table look-up to obtain an optimized voltage and pre-charge time of a gate drive circuit.

Abstract: An insulated gate bipolar transistor, comprising an anode second conductivity-type region and an anode first conductivity-type region provided on a drift region; the anode first conductivity-type region comprises a first region and a second region, and the anode second conductivity-type region comprises a third region and a fourth region, the dopant concentration of the first region being less than that of the second region, the dopant concentration of the third region being less than that of the fourth region, the third region being provided between the fourth region and a body region, the first region being provided below the fourth region, and the second region being provided below the third region and located between the first region and the body region.

Abstract: The present invention discloses a high-threshold power semiconductor device and a manufacturing method thereof. The high-threshold power semiconductor device includes, in sequence from bottom to top: a metal drain electrode, a substrate, a buffer layer, and a drift region; further including: a composite column body which is jointly formed by a drift region protrusion, a columnar p-region and a columnar n-region on the drift region, a channel layer, a passivation layer, a dielectric layer, a heavily doped semiconductor layer, a metal gate electrode and a source metal electrode. The composite column body is formed by sequentially depositing a p-type semiconductor layer and an n-type semiconductor layer on the drift region and then etching same. The channel layer and the passivation layer are formed in sequence by deposition. Thus, the above devices are divided into a cell region and a terminal region.

Abstract: An inductor current estimation method for a DC-DC switching power supply using a voltage sampling module, a data conversion module, a switching signal counting module, an inductor voltage calculation module and a digital filter module, comprising: processing an input voltage and an output voltage by the voltage sampling module and the data conversion module to obtain a converted input voltage and a converted output voltage which have a same number of bits; comparing a node voltage with a reference voltage, and then obtaining a duty cycle by the switching signal counting module; and then, outputting an average voltage of two terminals of an inductor and a parasitic resistor by the inductor voltage calculation module, and finally, obtaining an estimated inductor current by the digital filter module.

Abstract: A control method for a four-switch buck-boost converter is provided. The control method adopts four-stage control, and divides the load range into two sections and adopts different control strategies according to a critical load value corresponding to optimal control. In Boost mode, before the critical load, T1 and T2 are kept constant, T3 is a minimum value for realizing soft-switching, and T4 decreases with the increase of the load; when the critical load is reached, T4 drops to 0; and after the critical load, T1, T2, T3 and T increase with the load. In Buck mode, before the critical load, T2 and T3 are kept constant, T1 is a minimum value for realizing soft-switching, and T4 decreases with the increase of the load; when the critical load is reached, T4 drops to 0; and after the critical load, T1, T2, T3 and T increase with the load.

Abstract: A control method for a four-switch buck-boost converter is provided. The control method adopts four-stage control, and divides the load range into two sections and adopts different control strategies according to a critical load value corresponding to optimal control. In Boost mode, before the critical load, T1 and T2 are kept constant, T3 is a minimum value for realizing soft-switching, and T4 decreases with the increase of the load; when the critical load is reached, T4 drops to 0; and after the critical load, T1, T2, T3 and T increase with the load. In Buck mode, before the critical load, T2 and T3 are kept constant, T1 is a minimum value for realizing soft-switching, and T4 decreases with the increase of the load; when the critical load is reached, T4 drops to 0; and after the critical load, T1, T2, T3 and T increase with the load.

Abstract: An enhancement-mode N-channel and P-channel GaN device integration structure comprises a substrate, wherein an Al—N nucleating layer, an AlGaN buffer layer, a GaN channel layer and an AlGaN barrier layer are sequentially arranged on the substrate, and the AlGaN barrier layer and the GaN channel layer are divided by an isolation layer; a P-channel device is arranged on one side of the isolation layer and comprises a first P-GaN layer, a first GaN isolation layer and a first P+-GaN layer are sequentially arranged on the first P-GaN layer, a first source, a first gate and a first drain are arranged on the first P+-GaN layer, the first gate is inlaid in the first P+-GaN layer, and a gate dielectric layer is arranged between the first gate and the first P+-GaN layer; and an N-channel device is arranged on the other side of the isolation layer.

Abstract: A multi-phase high-precision current sharing control method applied to constant on-time control is provided, wherein a current difference between continuously sampled current of each line and mean current is processed by a PI compensation module and a low-pass filter module to obtain on-time regulation data. A high bit of the regulation data controls the value of counter reference Vref in an on-time control module, and a low bit controls the length of an enabled delay line in a delay line module. The counter timing control of the on-time control module is combined with the delay line timing control of the delay line module to improve the control precision of a DPWM. The method takes COT control of a Buck converter as a typical application. Compared with a multi-phase COT controller without a current-sharing mechanism, the method can improve the stability and reliability of the system.

Abstract: An enhancement-mode N-channel and P-channel GaN device integration structure comprises a substrate, wherein an Al—N nucleating layer, an AlGaN buffer layer, a GaN channel layer and an AlGaN barrier layer are sequentially arranged on the substrate, and the AlGaN barrier layer and the GaN channel layer are divided by an isolation layer; a P-channel device is arranged on one side of the isolation layer and comprises a first P-GaN layer, a first GaN isolation layer and a first P+-GaN layer are sequentially arranged on the first P-GaN layer, a first source, a first gate and a first drain are arranged on the first P+-GaN layer, the first gate is inlaid in the first P+-GaN layer, and a gate dielectric layer is arranged between the first gate and the first P+-GaN layer; and an N-channel device is arranged on the other side of the isolation layer.

Abstract: In the monolithically integrated GaN-based half-bridge circuit, a nucleation layer, a buffer layer, a channel layer and a barrier layer are sequentially provided on a conductive substrate, the barrier layer and the channel layer are separated by isolation layers, and a diode, an integrated capacitor, a low-side transistor, a high-side transistor, a first integrated resistor and a second integrated resistor are provided. The half-bridge circuit includes: a low-side transistor and a high-side transistor, wherein a drain of the low-side transistor is connected to a source of the high-side transistor and also connected to an output terminal Vout, and a substrate of the low-side transistor is connected to a substrate of the high-side transistor, wherein a series resistor is connected in parallel to a drain of the high-side transistor and a source of the low-side transistor.

Abstract: A multi-phase high-precision current sharing control method applied to constant on-time control is provided, wherein a current difference between continuously sampled current of each line and mean current is processed by a PI compensation module and a low-pass filter module to obtain on-time regulation data. A high bit of the regulation data controls the value of counter reference Vref in an on-time control module, and a low bit controls the length of an enabled delay line in a delay line module. The counter timing control of the on-time control module is combined with the delay line timing control of the delay line module to improve the control precision of a DPWM. The method takes COT control of a Buck converter as a typical application. Compared with a multi-phase COT controller without a current-sharing mechanism, the method can improve the stability and reliability of the system.

Abstract: A GaN power semiconductor device integrated with a self-feedback gate control structure comprises a substrate, a buffer layer, a channel layer and a barrier layer. A gate control area is formed by a first metal source electrode, a first P-type GaN cap layer, a first metal gate electrode, a first metal drain electrode, a second P-type GaN cap layer and a second metal gate electrode. An active working area is formed by the first metal source electrode, a third P-type GaN cap layer, a third metal gate electrode, a second metal drain electrode, the second P-type GaN cap layer and a second metal source electrode. The overall gate leaking current of the device is regulated by the gate control area, the integration level is high, the parasitic effect is small, and the charge-storage effect can be effectively relieved, thus improving the threshold stability of the device.

Abstract: A synchronous rectification control system and method for a quasi-resonant flyback converter are provided. The control system includes a switching transistor voltage sampling circuit configured to sample an output terminal voltage of the switching transistor to obtain a sampled voltage of the switching transistor; a sampling calculation module configured to obtain a dead-time based on the sampled voltage of the switching transistor and a preset relationship, the preset relationship being a correspondence between the duration of the sampled voltage of the switching transistor being below a first preset value and the dead-time during an on-time of a switching cycle of the switching transistor, the dead-time being a time from when the switching transistor is turned off to when the synchronous rectification transistor is turned on; and a control module configured to receive the dead-time and control switching of the synchronous rectification transistor based on the dead-time.

Abstract: A lateral double-diffused metal oxide semiconductor field effect transistor (LDMOS), including: a trench gate including a lower part inside a trench and an upper part outside the trench, a length of the lower part in a width direction of a conducting channel being less than that of the upper part, and the lower part extending into a body region and having a depth less than that of the body region; an insulation structure arranged between a drain region and the trench gate and extending downwards into a drift region, a depth of the insulation structure being less than that of the drift region.

Abstract: A flyback converter and an output voltage acquisition method therefor and apparatus thereof, wherein the output voltage acquisition method comprises the following steps: acquiring the reference output voltage of a flyback converter; sampling the current output voltage of the flyback converter within a reset time of each switching period among M continuous switching periods of the flyback converter, wherein M is a positive integer; and according to the reference output voltage and the current output voltage, sampling a dichotomy to successively approximate the current output voltage until the M switching periods are finished, and acquiring the output voltage of the flyback converter.

Abstract: Disclosed are a system and method for controlling an active clamp flyback (ACF) converter. The system includes: a drive module configured to control turning-on or turning-off of a main switching transistor SL and a clamp switching transistor SH; a main switching transistor voltage sampling circuit configured to sample a voltage drop between an input terminal and an output terminal of the main switching transistor SL; a first comparator connected to the main switching transistor voltage sampling circuit and configured to determine whether a sampled first sampling voltage is a positive voltage or a negative voltage; and a dead time calculation module configured to adjust, according to an output of the first comparator and a main switching transistor control signal DUTYL of a current cycle, a clamp switching transistor control signal DUTYH of next cycle outputted by the drive module.

Abstract: A laterally double-diffused metal oxide semiconductor device is provided, including: a drift region (3) having a first conductivity type; a first body region (10) disposed on the drift region (3) and having a second conductivity type, the first conductivity type and the second conductivity type being opposite conductivity types; a first conductivity type region (13) disposed in the first body region (10); a second body region (12) disposed in the first conductivity type region (13) and having the second conductivity type; a source region (11) disposed in the second body region (12) and having the first conductivity type; and a contact region (9) disposed in the first body region (10) and having the second conductivity type.