Abstract:
A lateral insulated gate bipolar transistor (IGBT) with a low turn-on overshoot current is provided to reduce a peak value of a current flowing through a device during turn-on of a second gate pulse while preventing a current capability and a withstand voltage capability from being degraded. The lateral IGBT includes: a buried oxygen arranged on a P-type substrate, an N-type drift region arranged on the buried oxygen, on which a P-type body region and an N-type buffer region are arranged, a P-type collector region arranged in the N-type buffer region, a field oxide layer arranged above the N-type drift region, a P-type well region arranged in the P-type body region, and a P-type emitter region and an emitter region arranged in the P-type well region, where inner boundaries of the foregoing 4 regions are synchronously recessed to form a pinch-off region. A gate oxide layer is arranged on a surface of the P-type body region, and a polysilicon gate is arranged on the gate oxide layer. The polysilicon gate includes a first gate located above the surface of the P-type body region and a second gate located above the pinch-off region and the N-type drift region. The first gate is connected to a first gate resistor, and the second gate is connected to a second gate resistor.
Abstract:
The invention discloses a self-adaptive synchronous rectification control system and a self-adaptive synchronous rectification control method of an active clamp flyback converter. The control system comprises a sampling and signal processing circuit, a control circuit with a microcontroller as a core and a gate driver. According to the control method, a switching-on state, an early switching-off state, a late switching-off state and an exact switching-off state of a secondary synchronous rectifier of the active clamp flyback converter can be directly detected, and the synchronous rectifier and a switching-on time of the synchronous rectifier in next cycle can be controlled according to a detection result. After several cycles of self-adaptive control, the synchronous rectifier enters the exact switching-on state, thus avoiding oscillation of an output waveform of the active clamp flyback converter.
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:
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 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:
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.