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:
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:
The invention provides a graphene channel silicon carbide power semiconductor transistor, and its cellular structure thereof. Characterized in that, a graphene strip serving as a channel is embedded in a surface of the P-type body region and two ends of the graphene strip are respectively contacted with a boundary between the N+-type source region and the P-type body region and a boundary between the P-type body region and the N-type drift region, and the graphene strip is distributed in a cellular manner in a gate width direction, a conducting channel of a device is still made of graphene; in the case of maintaining basically invariable on-resistance and current transmission capacity, the P-type body regions are separated by the graphene strip, thus enhancing a function of assisting depletion, which further reduces an overall off-state leakage current of the device, and improves a breakdown voltage.
Abstract:
A transverse ultra-thin insulated gate bipolar transistor having current density includes: a P substrate, where the P substrate is provided with a buried oxide layer thereon, the buried oxide layer is provided with an N epitaxial layer thereon, the N epitaxial layer is provided with an N well region and P base region therein, the P base region is provided with a first P contact region and an N source region therein, the N well region is provided with an N buffer region therein, the N well region is provided with a field oxide layer thereon, the N buffer region is provided with a P drain region therein, the N epitaxial layer is provided therein with a P base region array including a P annular base region, the P base region array is located between the N well region and the P base region, the P annular base region is provided with a second P contact region and an N annular source region therein, and the second P contact region is located in the N annular source region. The present invention greatly increases current density of a transverse ultra-thin insulated gate bipolar transistor, thus significantly improving the performance of an intelligent power module.
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. The dielectric layer, the heavily doped semiconductor layer, the metal gate electrode and the source metal electrode only exist in the cell region, and the passivation layer of the terminal region extends upwards and is wrapped outside the channel layer. This structure can increase a threshold voltage of the device, improve the blocking characteristics of the device and reduce the size of a gate capacitance.
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 control method for improving dynamic response of switch power is based on a closed-loop control system comprising a sampling module, a dynamic control module, an error calculation module, a PID module, a mode control module, and a PWM module. The sampling module samples an output voltage Vo, and the dynamic control module compares the output voltage Vo with a set maximum voltage Vomax, a set minimum voltage Vomin, and a reference voltage Vref, so as to determine whether to adopt a dynamic mode. In the dynamic mode, when the output voltage Vo changes greatly, the output voltage Vo is rapidly restored to a stable voltage by inputting large power or small power.
Abstract:
A transverse ultra-thin insulated gate bipolar transistor having current density includes: a P substrate, where the P substrate is provided with a buried oxide layer thereon, the buried oxide layer is provided with an N epitaxial layer thereon, the N epitaxial layer is provided with an N well region and P base region therein, the P base region is provided with a first P contact region and an N source region therein, the N well region is provided with an N buffer region therein, the N well region is provided with a field oxide layer thereon, the N buffer region is provided with a P drain region therein, the N epitaxial layer is provided therein with a P base region array including a P annular base region, the P base region array is located between the N well region and the P base region, the P annular base region is provided with a second P contact region and an N annular source region therein, and the second P contact region is located in the N annular source region. The present invention greatly increases current density of a transverse ultra-thin insulated gate bipolar transistor, thus significantly improving the performance of an intelligent power 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:
The present invention discloses a gate drive circuit for reducing a reverse recovery current of a power device, and belongs to the field of basic electronic circuit technologies. The gate drive circuit includes a high-voltage LDMOS transistor, a diode forming a freewheeling path when the diode is turned on or a low-voltage MOS transistor in anti-parallel connection with a body diode, and a voltage detection circuit. When the power device is turned off, a freewheeling current produced by an inductive load flows through a freewheeling diode, the voltage detection circuit detects that the freewheeling diode is turned on, and an output signal is processed by a control circuit, to cause the drive circuit to output a high level, so that channels of the power device and the high-voltage LDMOS transistor are turned on, the freewheeling current flows through the conductive channels, almost not through the freewheeling diode, and there is no reverse recovery current in the freewheeling diode at this time, thereby reducing the reverse recovery current of the power device.