公开(公告)号：US20180262186A1

公开(公告)日：2018-09-13

申请号：US15779432

申请日：2017-01-23

Applicant: SOUTHEAST UNIVERSITY ,  SOUTHEAST UNIVERSITY-WUXI INTEGRATED CIRCUIT TECHNOLOGY RESEARCH INSTITUTE

Inventor： Weifeng SUN ,  Yunwu ZHANG ,  Kuo YU ,  Jing ZHU ,  Shen XU ,  Qinsong QIAN ,  Siyang LIU ,  Shengli LU ,  Longxing SHI

IPC: H03K17/06 ,  H03K17/687 ,  H03K17/16

CPC classification number: H03K17/063 ,  H01L27/0727 ,  H01L29/1083 ,  H01L29/42368 ,  H01L29/7835 ,  H03K17/162 ,  H03K17/6871 ,  H03K19/0185 ,  H03K2217/0063 ,  H03K2217/0081

Abstract: Parasitic high-voltage diodes implemented by integration technology in a high-voltage level shift circuit are used for charging a bootstrap capacitor CB, wherein a power supply end of the high voltage level shift circuit is a high-side floating power supply VB, and a reference ground is a floating voltage PGD that is controlled by a bootstrap control circuit. A first parasitic diode DB1 and a second parasitic diode DB2 are provided between the VB and the PGD. The bootstrap control circuit is controlled by a high-side signal and a low-side signal.

公开(公告)号：US20250085315A1

公开(公告)日：2025-03-13

申请号：US18567382

申请日：2022-12-29

Applicant: SOUTHEAST UNIVERSITY

Inventor： Qinsong QIAN ,  Song DING ,  Chunyan NIE ,  Yuanhang ZHOU ,  Weifeng SUN ,  Longxing SHI

IPC: G01R19/00 ,  H02M1/00 ,  H02M3/335

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.

公开(公告)号：US20240266430A1

公开(公告)日：2024-08-08

申请号：US18577714

申请日：2022-12-29

Applicant: SOUTHEAST UNIVERSITY

Inventor： Long ZHANG ,  Weifeng SUN ,  Siyang LIU ,  Jie MA ,  Peigang LIU ,  Longxing SHI

IPC: H01L29/778 ,  H01L29/10 ,  H01L29/20 ,  H01L29/207

CPC classification number: H01L29/7787 ,  H01L29/1066 ,  H01L29/2003 ,  H01L29/207

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.

公开(公告)号：US20220069718A1

公开(公告)日：2022-03-03

申请号：US17420866

申请日：2020-06-19

Applicant: SOUTHEAST UNIVERSITY ,  CSMC TECHNOLOGIES FAB2 CO., LTD.

Inventor： Shen XU ,  Minggang CHEN ,  Wanqing YANG ,  Dejin WANG ,  Rui JIANG ,  Weifeng SUN ,  Longxing SHI

IPC: H02M3/335 ,  H02M1/38

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.

公开(公告)号：US20240266959A1

公开(公告)日：2024-08-08

申请号：US18566102

申请日：2022-09-26

Applicant: SOUTHEAST UNIVERSITY

Inventor： Qi LIU ,  Weiwei ZHAI ,  Leilei SHI ,  Qinsong QIAN ,  Weifeng SUN ,  Longxing SHI

IPC: H02M3/158 ,  H02M1/00 ,  H02M1/088

CPC classification number: H02M3/1582 ,  H02M1/0058 ,  H02M1/088

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.

公开(公告)号：US20220376094A1

公开(公告)日：2022-11-24

申请号：US17762212

申请日：2020-08-26

Applicant: SOUTHEAST UNIVERSITY ,  CSMC TECHNOLOGIES FAB2 CO., LTD.

Inventor： Long ZHANG ,  Jie MA ,  Yan GU ,  Sen ZHANG ,  Jing ZHU ,  Jinli GONG ,  Weifeng SUN ,  Longxing SHI

IPC: H01L29/739 ,  H01L29/08 ,  H01L29/10 ,  H01L29/06

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.

公开(公告)号：US20210194375A1

公开(公告)日：2021-06-24

申请号：US16617508

申请日：2018-09-28

Applicant: SOUTHEAST UNIVERSITY

Inventor： Qinsong QIAN ,  Shengyou XU ,  Qi LIU ,  Weifeng SUN ,  Shengli LU ,  Longxing SHI

IPC: H02M3/335 ,  H02M1/08

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.

公开(公告)号：US20200343810A1

公开(公告)日：2020-10-29

申请号：US16959015

申请日：2018-12-29

Applicant: CSMC TECHNOLOGIES FAB2 CO., LTD. ,  SOUTHEAST UNIVERSITY

Inventor： Shen XU ,  Minggang CHEN ,  Hao WANG ,  Jinyu XIAO ,  Wei SU ,  Weifeng SUN ,  Longxing SHI

IPC: H02M1/38 ,  H02M3/335 ,  H02M1/08

Abstract: An automatic dead zone time optimization system in a primary-side regulation flyback power supply CCM mode, comprising a closed loop formed by a control system, consisting of a single output DAC midpoint sampling module, a digital control module, a current detection module, a dead zone time calculation module and a PWM driving module, and a controlled synchronous rectification primary-side regulation flyback converter. By means of a DAC Sampling mechanism, a primary-side current is sampled to calculate a secondary-side average current, so as to obtain a primary-side average current Imid_p and a secondary-side average current Is(tmid) in the case of CCM; a secondary-side current is input into the dead zone time calculation module to obtain a reasonable dead zone time td; and finally, the PWM driving module is jointly controlled by a primary-side regulation loop and the obtained dead zone time td.

公开(公告)号：US20200336070A1

公开(公告)日：2020-10-22

申请号：US16959001

申请日：2018-12-29

Applicant: CSMC TECHNOLOGIES FAB2 CO., LTD. ,  SOUTHEAST UNIVERSITY

Inventor： Weifeng SUN ,  Rongrong TAO ,  Hao WANG ,  Jinyu XIAO ,  Wei SU ,  Shen XU ,  Longxing SHI

IPC: H02M3/335 ,  H03K5/24

Abstract: A method for improving the conversion efficiency of a CCM mode of a flyback resonant switch power supply, comprising: presetting a threshold value Tset, calculating a time interval Ttap between adjacent zero points during a present conducting time, outputting a switch-off signal at zero points, and comparing the time interval Ttap with the preset threshold value Tset; when Ttap>Tset, he present switch-off time to be less than a switch-off time of a previous cycle, outputting a switch-on signal; when Ttap=0, controlling the present switch-off time to be greater than a switch-off time of the previous cycle, outputting a switch-on signal; and when 0

公开(公告)号：US20200328689A1

公开(公告)日：2020-10-15

申请号：US16915524

申请日：2020-06-29

Applicant: CSMC TECHNOLOGIES FAB2 CO., LTD. ,  SOUTHEAST UNIVERSITY

Inventor： Shen XU ,  Wei WANG ,  Feng LIN ,  Boyong HE ,  Wei SU ,  Weifeng SUN ,  Longxing SHI

IPC: H02M3/335 ,  G01R19/165 ,  H03K5/24

Abstract: Provided is a dynamic control method that turns off a primary-side switching transistor when an output voltage exceeds an upper limit, and control the switching of a secondary-side synchronous rectification transistor with a fixed cycle and a fixed duty cycle. During the time that the synchronous rectification transistor is turned on, the energy of a load capacitor at the output end is extracted to the primary side, which causes the output voltage to drop rapidly and the overshoot voltage to decrease greatly.