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.
Abstract:
A high-current, N-type silicon-on-insulator lateral insulated-gate bipolar transistor, including: a P-type substrate, a buried-oxide layer disposed on the P-type substrate, an N-type epitaxial layer disposed on the oxide layer, and an N-type buffer trap region. A P-type body region and an N-type central buffer trap region are disposed inside the N-type epitaxial layer; a P-type drain region is disposed in the buffer trap region; N-type source regions and a P-type body contact region are disposed in the P-type body region; an N-type base region and a P-type emitter region are disposed in the buffer trap region; gate and field oxide layers are disposed on the N-type epitaxial layer; polycrystalline silicon gates are disposed on the gate oxide layers; and a passivation layer and metal layers are disposed on the surface of the symmetrical transistor. P-type emitter region output and current density are improved without increasing the area of the transistor.
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:
An automatic dead zone time optimization system in a primary-side regulation flyback power supply continuous conduction mode (CCM), including a closed loop formed by a control system, including a single output digital to analog converter (DAC) midpoint sampling module, a digital control module, a current detection module, a dead zone time calculation module and a pulse-width modulation (PWM) driving module, and a controlled synchronous rectification primary-side regulation flyback converter. A primary-side current is sampled using a DAC Sampling mechanism to calculate a secondary-side average current, so as to obtain a primary-side average current and a secondary-side average current, 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; and the PWM driving module is jointly controlled by a primary-side regulation loop and the obtained dead zone time.
Abstract:
A high-current, N-type silicon-on-insulator lateral insulated-gate bipolar transistor, including: a P-type substrate, a buried-oxide layer disposed on the P-type substrate, an N-type epitaxial layer disposed on the oxide layer, and an N-type buffer trap region. A P-type body region and an N-type central buffer trap region are disposed inside the N-type epitaxial layer; a P-type drain region is disposed in the buffer trap region; N-type source regions and a P-type body contact region are disposed in the P-type body region; an N-type base region and a P-type emitter region are disposed in the buffer trap region; gate and field oxide layers are disposed on the N-type epitaxial layer; polycrystalline silicon gates are disposed on the gate oxide layers; and a passivation layer and metal layers are disposed on the surface of the symmetrical transistor. P-type emitter region output and current density are improved without increasing the area of the 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:
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 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:
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 method for improving the conversion efficiency of a CCM mode of a flyback resonant switch power supply, comprising: presetting a critical value Tset, calculating a time interval Ttap between adjacent zero points in the current connection time, outputting a shutdown signal at the zero points, and comparing the time interval Ttap with the preset critical value Tset; when Ttap>Tset, controlling the current shutdown time to be less than the shutdown time of the preceding cycle and outputting a start signal; when Ttap=0, controlling the current shutdown time to be greater than the shutdown time of the preceding cycle and outputting a start signal; and when 0