Monolithic Power Systems Patent Grants

Single inductor dual output voltage converter and the method thereof

Granted: June 12, 2018
Patent Number: 9998005
A voltage converter provides a positive voltage and a negative voltage with a single inductor. The voltage converter has a first switch, a second switch, a third switch and a fourth switch switched periodically, wherein each switching period comprise a first time period, a second time period and a third time period, and wherein: during the first time period, the first switch and the fourth switch are turned on, whereas the second switch and the third switch are turned off; during the…

Switching mode power supply with adaptive frequency

Granted: May 22, 2018
Patent Number: 9979288
Switching mode power supply (SMPS) having a switch circuit and a controller. The switch circuit has an output inductor and a switch with a minimum on time. A control signal is generated by the controller to control the switching operation of the switch based on a clock signal with a switching frequency and an off signal. When the required on time of the switch is smaller than the minimum on time, the SMPS reduces the switching frequency adaptively and the actual on time of the switch is…

Method for forming stepped oxide on a substrate

Granted: May 22, 2018
Patent Number: 9978846
A method for forming a steeped oxide on a substrate is described: successively forming a first pad oxide layer, a nitride layer, a second pad oxide layer and a poly layer on the substrate; etching the poly layer to have an opening for the stepped oxide region; isotropically etching the second pad oxide layer to the nitride layer through the opening to form a stepped trench; isotropically etching the nitride layer to the first pad oxide layer through the opening to expand the stepped…

Buck-boost converter, the control circuit and the method thereof

Granted: May 8, 2018
Patent Number: 9966851
A buck-boost converter automatically chooses work mode between buck mode, boost mode and buck-boost mode, in response to an input voltage and an output voltage. The buck-boost converter is with simple structure, convenient mode transition and lower output voltage ripple.

Magnetic angular sensing system with side-shaft mounted sensor and the method thereof

Granted: April 17, 2018
Patent Number: 9945691
A magnetic angular sensing system has a magnet magnetized radially and a magnetic angular sensor for sensing the angular position of the magnet. The magnetic angular sensor is mounted in parallel to the axis of the magnet and is non-coplanar with the magnet. The magnetic angular sensor senses an angular position of the magnet based on a detected axial magnetic field component and a tangential magnetic field component of the magnetic field vector where the sensor mounted. This invention…

H-bridge bidirectional current sensing circuit

Granted: April 10, 2018
Patent Number: 9941816
A bidirectional current sensing circuit includes: a sensing resistor coupled between a load and a reference ground, a first and second auto-zero amplifiers coupled to the sensing resistor to sense the voltage across the sensing resistor, and an output transistor. One of the first and second auto-zero amplifiers operates in an output mode and the other of the first and second auto-zero amplifiers operates in a zeroing mode according to a polarity of a voltage across the sensing resistor.…

Multi-rail switching converter, control circuit and associated control method

Granted: April 10, 2018
Patent Number: 9941781
A multi-rail switching converter providing a plurality of output voltages has a master switching circuit, a plurality of slave switching circuits and a control circuit. The control circuit has an interleaving control circuit, the interleaving control circuit judges a phase zone of a corresponding slave switching circuit based on a switching control signal of the master switching circuit and a set signal of the corresponding slave switching circuit, and adjusts a turn-ON moment of the…

Method for fabricating LDMOS with reduced source region

Granted: April 10, 2018
Patent Number: 9941171
A method for fabricating a semiconductor device including: forming a block layer above a well region of a first doping type in a semiconductor substrate, wherein the block layer has an opening for defining a first region in an upper part of the well region and has sidewalls at sides of the opening; implanting dopants of a second doping type into the well region through the opening of the block layer to form the first region; implanting dopants of the first doping type into the first…

AC switch circuit and associated control method

Granted: April 3, 2018
Patent Number: 9935630
An AC switch circuit coupled between an AC input signal and an AC load has a first switch, a second switch, a driving circuit, and a power generation circuit. The first switch blocks a first half-cycle of the AC input signal when turned OFF, and the second switch blocks a second half-cycle of the AC input signal when turned OFF. The driving circuit provides a driving signal to control the first switch and the second switch based on an enable signal. The power generation circuit provides…

Smart LED driver and LED drive method

Granted: April 3, 2018
Patent Number: 9936548
A LED driver adopts one power stage to provide a constant drive current to drive a load, and to provide different power supply voltages to power a smart module according to a dimming signal input by users through the smart module. The LED driver provides high performance with simple circuit structure.

Method for fabricating LDMOS using CMP technology

Granted: April 3, 2018
Patent Number: 9935176
A method for fabricating a LDMOS device in a well region of a semiconductor substrate, including: etching a polysilicon layer above the well region through a window for a body region; and forming spacers at side walls of the polysilicon layer, to define positions of source regions in the well region.

Constant on-time switching converter with reference voltage adjusting circuit and controller thereof

Granted: March 20, 2018
Patent Number: 9923463
A COT switching converter includes a switching circuit having a main switch, an on-time control circuit configured to generate an on-time control signal, a comparing circuit, a logic circuit and a reference voltage adjusting circuit. The comparing circuit compares a reference voltage with a feedback signal indicative of output voltage of the switching circuit to generate a comparison signal. Based on the on-time control signal and the comparison signal, the logic circuit generates a…

Voltage converter integrated circuit with an integrated bootstrap capacitor

Granted: March 13, 2018
Patent Number: 9917584
A bootstrap circuit integrated to a voltage converter integrated circuit (IC) and a voltage converter IC for a switch mode voltage regulator. The bootstrap circuit is used to provide a bootstrap voltage signal for driving a high side switch of the voltage converter IC. The bootstrap circuit has a pre-charger and a bootstrap capacitor. The pre-charger provides a first bootstrap signal to pre-charge a control terminal of the high side switch, and the bootstrap capacitor provides a second…

Two-channel LED driver and the control method thereof

Granted: March 6, 2018
Patent Number: 9913332
A two-channel LED driver adopts one power stage to provide a constant drive current to drive a first channel LED and a second channel LED, and to provide a power supply voltages to power a smart module. The two-channel LED driver controls the total current flowing through the first channel LED and the second channel LED according to a first dimming signal input by users through the smart module, and controls the dimming ratio between the two channels according to a second dimming signal.…

Control method and circuit for resonant converters with capacitive protection

Granted: March 6, 2018
Patent Number: 9912244
Control method and circuit for resonant converters with capacitive protection. When a resonant converter enters into a capacitive mode, a high-side switch and a low-side switch of the resonant converter are turned off. After the high-side switch and a low-side switch are turned off for N switching cycles, the high-side switch is turned on once a current sense signal flowing through a resonant inductor of the resonant converter is increased to a zero-crossing threshold during an ascent…

Highly scalable multiphase power supply with constant on-time DC-DC converters

Granted: March 6, 2018
Patent Number: 9912240
A multiphase power supply includes several constant ON-time (COT) DC-DC converter integrated circuits (ICs). One of the COT DC-DC converter ICs generates a synchronization signal, which is received in parallel by the other COT DC-DC converter ICs. Two or more COT DC-DC converter ICs are turned ON at the same time in synchronization with the synchronization signal (e.g., an edge of a pulse of the synchronization signal) that is received in parallel and with another synchronization signal…

Soft start switching power supply system

Granted: March 6, 2018
Patent Number: 9912236
A switching power supply system includes a switching converter, to convert an input voltage into an output voltage and to generate a switching signal; a feedback circuit, to generate a feedback signal; an error amplifier to generate an error signal; a triangle signal generator to generate a triangle signal; a constant on time control circuit to receive error signal and the triangle signal, and to generate a constant on time control signal to control power switch; in the system. The…

Boost converter with short-circuit protection and method thereof

Granted: March 6, 2018
Patent Number: 9912145
A short-circuit protection method for a boost converter is disclosed. In this method, a switch of a switching circuit of the boost converter is turned on and a control voltage with a gradually increasing magnitude is supplied to control a short-circuit protection switch coupled between an input voltage and the switching circuit when the boost converter starts up. Then, a current flowing through the switch is detected and compared with a predetermined value. The switch is turned off and a…

Switching converter with smart frequency generator and control method thereof

Granted: February 13, 2018
Patent Number: 9891648
A control method of a switching converter, wherein the switching converter has a main transistor and is configured to provide an output signal. The control method includes: generating a feedback signal indicative of the output signal of the switching converter; generating a clock signal to determine the switching frequency of the main transistor; generating a control signal to control the main transistor based on the clock signal and the feedback signal; and detecting whether the on-time…

Lateral DMOS and the method for forming thereof

Granted: February 13, 2018
Patent Number: 9893146
A lateral DMOS device with peak electric field moved below a top surface of the device along a body-drain junction is introduced. The LDMOS has a deep body and a drift region formed by a series of P-type and N-type implants, respectively. The implant doses and depths are tuned so that the highest concentration gradient of the body-drift junction is formed below the surface, which suppresses the injection and trapping of hot holes in the device drain-gate oxide region vicinity, and the…