Texas Instruments Corporation

Chengdu Monolithic Power Systems Co., Ltd.

Yangwei Yu

Jian Liang

Yike Li

Chen Feng

Weicheng Zhang

Jian Zhao

Ming Luo

A DC-DC converter control circuit includes an error amplifier, a voltage-to-current conversion circuit, an oscillator circuit, and a pulse frequency modulation (PFM) control circuit. The error amplifier is configured to generate a difference voltage as a difference of an output voltage of the DC-DC converter circuit and a reference voltage. The voltage-to-current conversion circuit configured to convert the difference voltage to a difference current. The oscillator circuit is configured to generate a clock signal at a predetermined frequency for pulse width modulation. The PFM control circuit is configured to disable the oscillator circuit, based on the difference current, for PFM operation.

DC-DC converter with pulse modulation control circuit

A switch-mode power supply and control circuitry that reduces variation in the switching frequency of the power supply with changes in loading. In one example, a switch-mode power supply includes an inductor, a transistor, and control circuitry. The transistor is coupled to the inductor, and configured to charge the inductor. The control circuitry is coupled to the transistor. The control circuitry is configured to turn off the transistor for a first time period. The first time period is a function of voltage across the inductor during the first time period. The control circuitry is also configured to determine whether the switch-mode power supply is operating in continuous conduction mode or discontinuous conduction mode. The control circuitry is further configured to add a predetermined fixed interval to the first time based on the switch-mode power supply operating in discontinuous conduction mode.

Switch-mode power supply with frequency adjustment in discontinuous conduction mode

A voltage regulator circuit includes a first transistor, an inductor, and a diode. The inductor connects to the diode at a switch node. The voltage converter produces an output voltage that is larger than an input voltage. The first transistor has on and off states and electrically couples a node to ground when in the on state. An error amplifier circuit generates an error signal based on a difference between a reference voltage and a voltage indicative of the output voltage. The error signal causes the first transistor to transition from the on to the off state. An adaptive off-time generator circuit couples to the input voltage node, and generates a signal to cause the first transistor to transition from the off to the on state. The time the first transistor is in the off state is inversely proportional to the time the first transistor is in the on state.

Voltage regulator with an adaptive off-time generator

A drive and control circuit for motor system and the method thereof are disclosed. The motor system could be applied in a cooling device, wherein the motor system comprises a rotor, a coil and a bridge circuit. The drive and control circuit comprises a control unit, a state detecting circuit, a load determining circuit, and a startup setting circuit. The startup setting circuit makes the motor run with the maximum torque, thus to make the motor system start up easily and quickly. The load determining circuit detects the load of the motor system, thus to generate a load determining signal to determine the speed of the motor system. The control unit could be realized with few components so as to save the costs.

Growing community of inventors

Hangzhou, China

Yangwei Yu