Shanghai Awinic Technology Co., Ltd

Chiphomer Technology Limited

Jiantao Cheng

Liming Du

Haijun Zhang

Hongjun Sun

Zhifei Yang

Xucheng Luo

Jianwei Hu

Wei Yao

Zhong Zhang

Yan Jiang

Ke Wu

Tao Cheng

Jianing Zhou

Yongqiang He

Yongqing Qiao

Chuankui Wu

Chaoqun Wu

Disclosed are a digital audio power amplifier and a power amplifier loop. The power amplifier loop comprises an operational amplifier U, a capacitor C, a power amplifier output stage, a resistor R, a resistor Rand a noise control unit, wherein an inverting input end of the operational amplifier Uis respectively connected to one end of the capacitor C, one end of the noise control unit and an output end of a preceding DAC current source; an output end of the operational amplifier Uis respectively connected to a control end of the power amplifier output stage and the other end of the capacitor C; an output end of the power amplifier output stage is successively grounded by means of the resistors R, R; the other end of the noise control unit is connected to a connection point between the resistors R, R; the resistance values of the resistors R, Rare set to satisfy R/R=(N−2)/2, where N>2; the reference voltage of the operational amplifier Uis equal to PVDD/N, with PVDD being a power supply voltage of the power amplifier output stage; and the noise control unit is a resistor module. The present application ensures the normal operation of the digital audio power amplifier.

Digital audio power amplifier and power amplifier loop

A current detection circuit and method for protecting a speaker, and a chip are provided. The current detection circuit includes a current detection module and an analog-to-digital converter. The current detection module samples a current flowing through the speaker based on current mirror technology, and converts the current into a voltage to output a first voltage signal and a second voltage signal. The analog-to-digital converter converts the first voltage signal and the second voltage signal into a PDM code, to calculate a current parameter of the speaker.

Current detection circuit, chip, and current detection method used for speaker protection

A terminal control system and method, and a terminal device are provided. The terminal control system includes: a detection chip and at least one terminal key arranged on a side surface of a terminal device. The detection chip is connected to the terminal key. The terminal key is configured to generate an inductive capacitance and an interelectrode capacitance corresponding to an external control instruction, in response to a reception of the external control instruction. The detection chip is configured to detect the inductive capacitance and the interelectrode capacitance; determine inductive capacitance variation corresponding to the inductive capacitance and interelectrode capacitance variation corresponding to the interelectrode capacitance; determine a control type corresponding to the control instruction according to the inductive capacitance variation and the interelectrode capacitance variation; and trigger the terminal device to perform a control operation corresponding to the control type.

Terminal control system and method, and terminal device

A bootstrap circuit supporting fast charging and discharging and a chip. A voltage measurement module () and a switch module () are arranged, and the voltage measurement module () controls an operating state of the switch module (); during charging, under a specific condition, the switch module () is enabled to be in an on state so as to achieve fast charging of a voltage output end; and during discharging, the purpose of fast discharging is achieved by means of a second field effect transistor (MP) arranged in the bootstrap circuit.

Bootstrap circuit supporting fast charging and discharging and chip

The present disclosure provides a current detection circuit for a loudspeaker, comprising a first detection resistor RSP, a second detection resistor RSN, a sampling selection circuit, an input selection circuit, and a processing circuit. By adding the sampling selection circuitand the input selection circuit, voltages on two ends of the corresponding detection resistors (RSP, RSN) are sampled according to the fact that potential differences of an output stage VOP and an output stage VON of a class-D audio power amplifierare in different semi-periods, and the current of the loudspeakeris obtained through processing, thereby detecting the current of the loudspeakerwithout adding an anti-clipping distortion function to the class-D audio power amplifier

Current detection circuit for loudspeaker

A protection circuit is provided. A control circuit receives an input voltage. In a case that the input voltage is lower than a negative threshold voltage, the control circuit outputs a first control voltage to a surge bleeder circuit through a first output end of the control circuit, to control the surge bleeder circuit to discharge the input voltage and output a first bleeder current. In a case that the input voltage is higher than a positive threshold voltage, the control circuit outputs a second control voltage to the surge bleeder circuit through a second output end of the control circuit, to control the surge bleeder circuit to discharge the input voltage and output a second bleeder current.

Protection circuit with bidirectional surge protection

A load switch integrated circuit and an electronic device are provided. In a case that a surge voltage is applied to an input of the load switch integrated circuit, a surge detection circuit controls a first discharging unit to be switched on to discharge surge energy from an input of the load switch integrated circuit to the ground, and controls a first switch transistor and a second discharging unit to be switched on through a control circuit to discharge surge energy to an output of the load switch integrated circuit to the ground. Compared with a case that surge energy is discharged only by a surge protection circuit in the conventional technology, surge energy is discharged via two paths, and a circuit area is smaller than that in the conventional technology in a case that there is large surge energy to be resisted.

Load switch integrated circuit and electronic device

A power supply conversion circuit is provided, which includes: a first voltage clamping module configured to decrease an input voltage to a preset low voltage; a boost module configured to increase the input voltage or the preset low voltage to a target voltage; a second voltage clamping module configured to maintain the target voltage within a preset voltage range; a filter module configured to filter out ripples in the target voltage; and at least one output module, each of which is configured to supply power to a load. Compared with a conventional LDO integrated circuit, the circuit can provide multiple output power supplies, and it is only required to additionally arrange one field effect transistor for one more output power supply. Therefore, the power supply conversion circuit has a simple structure, is expandable easily and is applicable to an analog integrated circuit requiring multiple output power supplies.

Power supply conversion circuit

An adaptive capacitive touch sense control circuit includes a voltage buffer, a current setting resistor, a current mirror, a capacitor, a start comparator, an end comparator and a time-to-digital converter. The capacitor is connected with the current setting resistor. The circuit further includes a latch with a first control switch and a second control switch. The current setting resistor is switched between the ground and a voltage source through a switching element, so that when the current setting resistor is grounded, the first control switch is closed and the second control switch is opened, and when the current setting resistor is connected with the voltage source, the second control switch is closed and the first control switch is opened. An adaptive charging mode is adopted to sense a capacitance variation with a great ability of interference recognition, a simple structure, low power consumption and real time processing.

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Shanghai, China

Jiantao Cheng