Abstract: A diagnostic system for an inverter module includes a motor control module configured to determine operating characteristics of the inverter module. The operating characteristics include of at least one of a voltage, a current, and a switching frequency associated with operation of the inverter module. A diagnostic module is configured to receive the operating characteristics of the inverter module, estimate at least one junction temperature of a component of the inverter module based on the operating characteristics, calculate a health indicator of the inverter module based on the estimated junction temperature, and selectively output an alert based on the calculated health indicator.

Abstract: A switch mode power supply includes a bootstrap circuit, control circuits, and an auxiliary winding coupled to the bootstrap circuit and configured to supply power to the control circuits after startup of the power supply. The bootstrap circuit is configured to supply power to the control circuits during startup and includes an isolation circuit to limit current flow between the starting capacitor and the control circuits while the starting capacitor is charged to a starting voltage by the high voltage input. During the initial charge of the starting capacitor, the control circuits do not have power to provide the initial functionality of the power supply. Once the starting capacitor is charged to the starting voltage, the isolation circuit is activated to allow current flow that powers the control circuits during the remainder of the startup until the auxiliary winding is able to power the control circuits.

Abstract: A switched mode power supply (SMPS) includes a filter (202), a power factor correction (PFC) circuit (204), and a control circuit (206, 406) configured to determine various electrical parameters of the SMPS. In some embodiments, the control circuit (206, 406) is configured to determine a power line frequency and an AC input voltage based on an AC line voltage and an AC neural voltage. In other embodiments, the control circuit (206, 406) is configured to determine an AC input current based on a reactive current flowing through the filter (202) and a PFC AC current. In further embodiments, the control circuit (206, 406) is configured to report a value of an electrical parameter if value is determined to be accurate. Other example switch mode power supplies, control circuits and methods are also disclosed.

Abstract: Systems and methods for efficient power conversion in a power supply in a power distribution system are disclosed. In particular, a low frequency transformer having high conversion efficiency is coupled to an input from a power grid. An output from the transformer is rectified and then converted by a power factor correction (PFC) converter before passing the power to the distributed elements of the power distribution system. By placing the transformer in front of the PFC converter, overall efficiency may be improved by operating at lower frequencies while preserving a desired power factor and providing a desired voltage level. The size and cost of the cabinet containing the power conversion circuitry is minimized, and operating expenses are also reduced as less waste energy is generated.

Abstract: An integrated single stage ac-dc driver for powering LED loads includes a boost converter operating in a Discontinuous Conduction Mode, DCM, comprising a half-bridge, and a Zeta Asymmetrical Half Bridge, ZAHB, integrated with the boost converter such that the boost converter and the ZAHB share the half-bridge to perform power factor control, PFC, with a fixed duty cycle and control an output voltage.

Abstract: A power supply circuit sets a precharge current flowing through a first load device and a precharge current flowing through a second load device during charging to a first allowable current or less, thereafter sets the precharge current flowing through the first load device to the first allowable current or less, sets the precharge current flowing through the second load device to the second allowable current or less, and sets a maximum value of the precharge current flowing through the second load device to be larger than the first allowable current.

Abstract: A DC-DC power conversion system includes a resonant switched-capacitor converter and a controller. The resonant switched-capacitor converter is switched between a first state and a second state to generate an output voltage, and includes an input terminal, a resonant tank, an output capacitor, a first set of switches and a second set of switches. The input terminal is used to receive an input voltage. The output capacitor is used to generate the output voltage. The first set of switches is turned on in the first state and turned off in the second state according to a first control signal. The second set of switches is turned on in the second state and turned off in the first state according to a second control signal. The controller adjusts the first control signal and the second control signal according to the output voltage.

Abstract: A power converter for providing a negative voltage is provided. A coupling controller circuit receives a digital control signal and provides a control signal. A reverse voltage converter circuit receives the control signal and provides a reverse voltage. The reverse voltage converter circuit includes a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a seventh switch, an eighth switch, a coupling control signal triggering circuit and a pulse width modulation circuit. A first reverse logic circuit is connected to a second reverse logic circuit. The second reverse logic circuit is connected to the pulse width modulation circuit and is configured to provide a trigger signal to the pulse width modulation circuit. The pulse width modulation circuit turns on or off the reverse voltage converter circuit according to the trigger signal.

Abstract: A power converter is disclosed. The power converter includes a switching circuit coupled to a capacitor and further coupled to a regulated power supply node via an inductor. The switching circuit is configured to magnetize the inductor, using the capacitor, in response to activation of a first control signal, and further configured to charge the capacitor, using an input power supply, in response to activation of a second control signal. A control circuit is configured to activate the first control signal based on a comparison of a first threshold value and a current flowing in the inductor. The control circuit is further configured to activate the second control signal based on a comparison of a second threshold value and the current flowing in the inductor.

Abstract: A power converter including a piezoelectric resonator. The power converter includes a first transistor coupled between an input terminal and a first plate of the piezoelectric resonator, and a second transistor coupled between the first plate of the piezoelectric resonator and an output terminal. A load may be coupled at the output terminal. Controller circuitry has inputs coupled to the input node, the output node, and to the first plate of the piezoelectric resonator, and outputs coupled to control terminals of the first and second transistors. The controller circuitry operates to turn on the first transistor responsive to a comparison of voltages at the first plate and the input terminal, turn on the second transistor responsive to a comparison of voltages at the first plate and the output terminal, and turn off one of the first and second transistors responsive to an output level at the output terminal.

Abstract: A deadtime control scheme for improving buck converter light load efficiency.

Abstract: The present disclosure aims to avoid a situation where a drive unit to be used for precharge does not drive due to a drop in power supply voltage. The power supply device is provided with the first voltage conversion unit and the control unit. The first voltage conversion unit performs a third voltage conversion operation in which a voltage applied to a second conductive path is boosted and an output voltage is output to a first conductive path to which a capacitive component is electrically connected. The control unit supplies the third control signal to only some of the plurality of first voltage conversion units, thereby causing the some of the first voltage conversion units to perform the third voltage conversion operation.

Abstract: According to one configuration, an inductor device comprises: core material and one or more electrically conductive paths. The core material is magnetically permeable and surrounds (envelops) the one or more electrically conductive paths. Each of the electrically conductive paths extends through the core material of the inductor device from a first end of the inductor device to a second end of the inductor device. The magnetically permeable core material is operative to confine (guide, carry, convey, localize, etc.) respective magnetic flux generated from current flowing through a respective electrically conductive path. The core material stores the magnetic flux energy (i.e., first magnetic flux) generated from the current flowing through the first electrically conductive path.

Abstract: A power supply device includes a switching converter, an inductor, and a linear voltage regulator. The inductor is electrically connected between a first switching node and a second switching node of the switching converter. The power supply device is configured such that when the switching converter is in an ON state the inductor is charged with a charging current. The power supply device is further configured such that when the switching converter is in an OFF state, the switching converter modulates an input voltage to generate a positive-bias output voltage at a positive-bias output node, the charging current flows from the inductor such that a negative input voltage is generated at a linear voltage regulator input node, and the linear voltage regulator regulates the negative input voltage to generate a negative-bias output voltage at a negative-bias output node.

Abstract: A driver circuit controls a half-bridge that includes a high-side power switch and a low-side power switch. The driver circuit may comprise a high-side compare unit configured to determine a first drain-to-source voltage, wherein the first drain-to-source voltage is associated with the high-side power switch when the high-side power switch is ON, and a low-side compare unit configured to determine a second drain-to-source voltage, wherein the second drain-to-source voltage is associated with the low-side power switch when the low-side power switch is ON. The high-side compare unit may be further configured to determine a third drain-to-source voltage, wherein the third drain-to-source voltage is associated with the high-side power switch when the high-side power switch is OFF, and the low-side compare unit may be further configured to determine a fourth drain-to-source voltage, wherein the fourth drain-to-source voltage is associated with the low-side power switch when the low-side power switch is OFF.

Abstract: A power supply circuit for a switching mode power supply, having: a charging capacitor coupled to an auxiliary winding; a power supply diode coupled to a power supply capacitor, wherein the charging capacitor has a connecting terminal coupled to the power supply diode, and the charging capacitor and the power supply diode are serially coupled between the auxiliary winding of the switching mode power supply and the power supply capacitor; and a power supply switch coupled between the connecting terminal and a primary ground of the switching mode power supply.

Abstract: Described is a hybrid electronic and magnetic structure that enables a transformer with fractional and reconfigurable effective turns ratios (e.g. 12:0.5, 12:?, 12:1, and 12:2) and hereinafter referred to as a Variable-Inverter-Rectifier-Transformer (VIRT). A VIRT is valuable in converters having wide operating voltage ranges and high step-up/down, as it offers a means to reduce turns count and copper loss within a transformer while facilitating voltage doubling and quadrupling. Such characteristics are beneficial for reducing the size of a transformer stage in many power electronics applications, such as USB wall chargers. In embodiments, a VIRT comprises a plurality of switching cells distributed around a magnetic core and coupled to half-turns wound through that core. By controlling operating modes of the switching cells, it is possible to gain control over flux paths and current paths in the transformer.

Abstract: A neutral point clamped inverter with an upper half-bridge and a lower half-bridge, wherein each half-bridge has an inner transistor and an outer transistor, where the inner transistor of the upper half-bridge is configured to interact with the outer transistor of the upper half-bridge such that a signal that reproduces the switch state of the inner transistor is coupled into an actuation circuit for switching the outer transistor and influences the switch state of the outer transistor.

Abstract: Embodiments of the present application disclose a multi-level inverter clamping modulation method and apparatus, and an inverter. Switching elements of an inverter are controlled when an output voltage of the inverter crosses zero, and switching elements in each inverter bridge arm of an active clamp multi-level inverter include an internal tube, an external tube, and a clamping tube. The internal tube and the external tube are connected in series between a positive bus and a negative bus, the clamping tube is connected between a common terminal of the internal tube and the external tube and a bus, the internal tube is a low-frequency switching element, and the external tube and the clamping tube are high-frequency switching elements.

Abstract: A vibration-driven energy harvesting element that outputs an alternating current power from an output line, due to vibration from outside includes: an intermediate electrode that is not connected to the output line; a plurality of electret electrodes, each electret electrode being arranged to face the intermediate electrode and having an electret on at least a part of a surface of the electret electrode on a side facing the intermediate electrode; a holding unit that holds the intermediate electrode and the plurality of electret electrodes such that the intermediate electrode and the plurality of electret electrodes can vibrate with respect to each other; and a charge injector that injects a charge having characteristics opposite to a charge of the electrets formed in the surfaces of the plurality of electret electrodes, to the intermediate electrode.

Abstract: A piezoelectric drive device includes a piezoelectric element, a vibrating plate with a concave portion provided in a side surface, and a projecting portion provided between two side surfaces of the concave portion and having a spherical shape, an elliptical shape, or an egg shape, wherein a plurality of the piezoelectric elements and a plurality of the vibrating plates are stacked, and the concave portion includes a bottom surface.

Abstract: The present disclosure relates to an electromechanical linear drive having a housing, an electromechanical drive unit, a transmission element which is coupled to the electro-mechanical drive unit, and an element to be driven which is in frictional contact with the transmission element, where the transmission element is mounted on at least two bearing points with respect to the housing. Improved accessibility to the element to be driven and a longer adjustment path of the element to be driven can be achieved by placing the element to be driven in frictional contact with the transmission element at a point of engagement outside of all bearing points.

Abstract: Systems, methods, and computer-readable media are disclosed for haptic feedback devices with reduced power consumption. In one embodiment, an example device may include a first spring, a mass coupled to the first spring, and a resonant piezoelectric actuator coupled to the first spring. The resonant piezoelectric actuator may be configured to impart a force on the mass via the first spring responsive to an applied voltage. The device may include a power source configured to supply the applied voltage to the resonant piezoelectric actuator, where motion of the mass generates vibration.

Abstract: A determination method and apparatus for a brushless direct current counter-electromotive force zero crossing point threshold and a storage medium, the method includes detecting counter-electromotive force zero crossing point time intervals of two adjacent sectors of a brushless direct current electric motor to obtain at least two first time intervals; utilizing the obtained at least two first time intervals to determine errors of a counter-electromotive force zero crossing point; converging the determined errors of the counter-electromotive force zero crossing point to obtain a counter-electromotive force zero crossing point threshold correction increment; and utilizing the obtained counter-electromotive force zero crossing point threshold correction increment to determine a counter-electromotive force zero crossing point threshold.

Abstract: A motor control device includes: a plurality of sensors detecting a rotation position of a rotor and outputting a position detection signal; a rotational speed determination part determining whether a rotational speed of a brushless motor is equal to or less than a predetermined threshold value based on the position detection signal; and a motor control part. An energization control part included in the motor control part uses, between a first mode and a second mode, different sensor signals serving as a trigger for an energization timing of each phase. In the first mode, an energization timing to a second phase is advanced relative to a timing at which the position detection signal of a first sensor turns on. In the second mode, an energization timing to the second phase is retarded relative to a timing at which the position detection signal of the first sensor turns on.

Abstract: An object of the present invention is to provide a winding switching device capable of enhancing the reliability of electrical contact between a movable unit and a fixed unit, and a rotating electrical machine drive system including such a winding switching device.

Abstract: Controllers for controlling hybrid motor drive circuits configured to drive a motor are provided herein. A controller is configured to drive the motor using an inverter when a motor commanded frequency is not within a predetermined range of line input power frequencies, and couple line input power to an output of the inverter using a first switch device when the motor commanded frequency is within the predetermined range of line input power frequencies.

Abstract: A motor control apparatus receives a DC power source through a DC terminal and is coupled to a motor. The motor control apparatus includes a brake, an inverter, and a controller. The brake is coupled to the inverter. The brake includes an energy-consuming component and a switch component. The controller controls the inverter to convert the DC power source to drive the motor. When the controller determines that the DC power source is interrupted, the controller stops controlling the inverter, and the switch component is self-driven turned on so that a back electromotive force generated by the motor is consumed through the energy-consuming component.

Abstract: The present subject matter refers a discharge circuit for a smoothing capacitor within a power-distribution-unit. The discharge circuit comprises a first sub-circuit connected in parallel to a DC-Link capacitor, said first sub-circuit in turn comprises a series connection of a first switching element (SE) and a first discharge resistor, wherein the DC-link capacitor is connected in parallel to a power supply. A second sub-circuit is connected in parallel to the DC-Link capacitor and comprises a series connection of a second switching element (SE) and a second discharge resistor. A control device is configured to control the plurality of SEs within the sub-circuits by scheduling switching of the plurality of SEs. Such scheduling comprises switching ON of the second SE after a switching ON of the first SE for enabling a discharging of the DC link capacitor within a predetermined duration.

Abstract: A motor control device including a PWM control part is provided. The PWM control part has a two-phase complementary PWM control part, and when driving opening and closing of an opening/closing body, PWM-controls upper switching elements and lower switching elements of three phases in a three-phase inverter circuit based on an energization mode that sequentially switches among energized phases, which are two of the three phases, and a non-energized phase, which is a remaining one phase. The two-phase complementary PWM control part, in one of the energized phases, controls one of the upper switching element and the lower switching element by a PWM signal, and controls the other by a complementary PWM signal having a polarity opposite to the PWM signal, and, in the non-energized phase, controls one of the upper switching element and the lower switching element to be off, and controls the other by the complementary PWM signal.

Abstract: A power conversion device includes an inverter, a current detector, a frequency analysis processor, a storage, a determination unit, a reference rotational rate change unit, and a rate controller. The determination unit determines a frequency at which a signal component having a magnitude exceeding a prescribed value has been detected among frequency components of a load current, generates restriction information for excluding a reference rotational rate for a rotational rate corresponding to the detected frequency based on a determination result after the determination, and causes the storage to store the generated restriction information. The reference rotational rate change unit changes a reference rotational rate of an electric motor so that mechanical resonance of the detected frequency is avoided based on the stored restriction information. The rate controller controls a rotational rate of the inverter using the changed reference rotational rate.

Abstract: A motor controller 100-1 includes an inverter, a current detection unit, a current detector, and a PWM signal generator.

Abstract: A control unit for controlling a motor of an oil pump. The control unit includes a receiving unit configured to receive a target pressure, a first determination unit configured to determine a torque from the target pressure and a speed of the motor via a first characteristic map, a second determination unit configured to determine a motor phase current from the determined torque via a second characteristic map, and an output unit configured to output the determined motor phase current.

Abstract: A system and method for shaping the trajectory of a motion command to reduce the effects of a load on performance of a motor dynamically modifies the motion profile in real time to limit the reference signals in the motion profile to feasible commands. A load observer determines an estimated disturbance acceleration. The estimated disturbance acceleration includes the dynamics of the controlled load and is used to modify a maximum and a minimum limit for the acceleration reference. The acceleration limits are, in turn, used to determine velocity limits. The motion profile and modified acceleration and velocity limits are provided to a state filter which determines a new motion profile for use by the motor drive to control operation of a motor and to control the load connected to the motor.

Abstract: A current detection unit includes current detection elements provided to phases on a high potential side of an upper arm element or on a low potential side of a lower arm element. A detection target element is the upper arm element or the lower arm element to which the current detection elements are provided. A target duty is a duty ratio of the detection target element. The control unit includes a current acquisition unit, an energization control unit, and an abnormality determination unit. The current acquisition unit acquires a current detection value from the current detection unit. The abnormality determination unit performs an abnormality determination based on the current detection value. The abnormality determination unit varies a determination threshold, which is used for the abnormality determination based on the current detection value, according to the target duty.

Abstract: A rotating machine power conversion device is obtained which achieves operational continuation in a rotational speed range in which the operational continuation is enabled, even when a single phase of an electrical power conversion device made of switching devices causes a disconnection or turn-off failure. The rotating machine power conversion device comprises: a normality-case/abnormality-case current control device selection device for transferring between a normality-case current control device and an abnormality-case current control device in accordance with a determination result of an abnormality determination device; and an abnormality-case current control device/power conversion halt device selection device, using a rotational speed calculation device, for transferring between the abnormality-case current control device used when a rotational speed is lower than that being prespecified, and the power conversion halt device used when a rotational speed is higher than that being prespecified.

Abstract: This system is directed to a mobile platform having a power array carried by the mobile platform, connected to a distribution hub adapted to provide power to a base power source; an input controller having input computer readable instructions adapted to deliver power to a set of storage units from the base power source, the set of storage power units carried by the mobile platform; an output controller connected to the set of storage units having output computer readable instructions adapted to receive charge requirements from a load connected to the output controller, retrieving from a device lookup table included in the output controller a load type having charge specifications and delivering power to the load according to the charge specifications; and, an external power source connected to the distribution bus for proving power to the base power source from the external power source.

Abstract: Solar trackers that may be advantageously employed on sloped and/or variable terrain to rotate solar panels to track motion of the sun across the sky include bearing assemblies and other mechanical features configured to address mechanical challenges posed by the sloped and/or variable terrain that might otherwise prevent or complicate use of solar trackers on such terrain.

Abstract: Systems, apparatuses, and methods are described for melting snow from a surface of a power source. The power source may be a photovoltaic (PV) module.

Abstract: A solar panel apparatus having an upper frame and a lower frame, the upper and lower frames being pivotally connected to one another via a hinge. The upper frame contains a solar panel, and the lower frame contains a plurality of louvres. The plurality of louvres is configured to rotate as the angle of the upper frame is adjusted relative to the sun. Dividing walls inside each of the upper and lower frames are configured to allow warm air to flow from behind the louvres, which are black on their front faces to absorb solar rays, upward to behind the solar panel, thereby warming the solar panel and melting any snow or ice from the front surface of the solar panel. Air vents in both the upper and lower frames prevent the apparatus from overheating.

Abstract: A temperature-controlled RF resonator. The resonator includes an insulating thermal enclosure within which are implemented: at least one resonant element configured to deliver an RF output signal when supplied with an RF input signal; at least one heating element configured to supply thermal energy within the thermal enclosure when the at least one heating element is powered by an LF electric power signal; and at least one temperature sensor configured to deliver an LF electric measurement signal as a function of the temperature inside the thermal enclosure. Such an RF resonator has at least one input/output port crossing the insulating thermal enclosure and propagating at least: one signal from among the RF signals; and another signal from among the LF electric signals.

Abstract: An oscillator includes a resonator, sustaining circuit and detector circuit. The sustaining circuit receives a sense signal indicative of mechanically resonant motion of the resonator generates an amplified output signal in response. The detector circuit asserts, at a predetermined phase of the amplified output signal, one or more control signals that enable an offset-reducing operation with respect to the sustaining amplifier circuit.

Abstract: A system includes a first differential amplifier and a first transformer with a primary coil coupled to an output of the first differential amplifier and with a secondary coil coupled to a load. The system also includes a second differential amplifier and a second transformer with a primary coil coupled to an output of the second differential amplifier and with a secondary coil coupled in series with the secondary coil of the first transformer. The system also includes a tuning network coupled to a center tap node between the secondary coil of the first transformer and the secondary coil of the second transformer.

Abstract: Disclosed is envelope tracking circuitry having an envelope tracking integrated circuit (ETIC) coupled to a power supply to provide an envelope tracked power signal to a power amplifier (PA) with a filter equalizer configured to inject an error-correcting signal into the ETIC in response to equalizer settings. Further included is PA resistance estimator circuitry having a first peak detector circuit configured to capture within a window first peaks associated with a sense current generated by the ETIC, a second peak detector circuit configured to capture within the window second peaks associated with a scaled supply voltage corresponding to the envelope tracked power signal, comparator circuitry configured to receive the first peaks and receive the second peaks and generate an estimation of PA resistance, and an equalizer settings correction circuit configured to receive the estimation of PA resistance and update the equalizer settings in response to the estimation of PA resistance.

Abstract: Apparatus and methods for a multiclass, broadband, no-load-modulation power amplifier are described. The power amplifier (500) may include a main amplifier (532) operating in a first amplification class and a plurality of peaking amplifiers (536, 537, 538) operating in a second amplification class. The main amplifier (532) and peaking amplifiers (536, 537, 538) may operate in parallel on portions of signals derived from an input signal to be amplified. The main amplifier (532) may see no modulation of its load impedance between a fully-on state of the power amplifier (all amplifiers amplifying) and a fully backed-off state (peaking amplifiers idle). By avoiding load modulation, the power amplifier (500) can exhibit improved bandwidth and efficiency compared to conventional Doherty amplifiers.

Abstract: In some implementations, there is provided an apparatus comprising a resonant amplifier circuit including a first inductor having a first inductive input and a first inductive output; a second inductor having a second inductive input and a second inductive output; a first switch coupled to the first inductive output; and a second switch coupled to the second inductive output, wherein the first switch and the second switched are driven out of phase, wherein the first inductor is configured to be resonant with a first capacitance associated with the first switch, and wherein the second inductor is configured to be resonant with a second capacitance associated with the second switch. Related systems and articles of manufacture are also provided.

Abstract: The present disclosure relates to chopper amplifier circuits with inherent chopper ripple suppression. Example implementations can realize a doubly utilized chopper amplifier circuit that is a current-saving circuit with a wake-up function that is capable of providing a self-wake signal in order to change into a fast, low-jitter/low-latency mode, and to provide a wake-up signal for a sleeping microprocessor or a system in response to signal changes.

Abstract: A circuit for startup of a multi-stage amplifier circuit includes a pair of input nodes and at least two output nodes configured to be coupled to a multi-stage amplifier circuit. A startup differential stage includes a differential pair of transistors having respective control terminals coupled to the pair of input nodes, and each transistor in the differential pair of transistors has a respective current path therethrough between a respective output node and a common source terminal. The startup differential stage is configured to sense a common mode voltage drop at a first differential stage of the multi-stage amplifier circuit. Current mirror circuitry includes a plurality of transistors coupled to the common terminal of the differential pair of transistors and coupled to two output nodes of the at least two output nodes.

Abstract: Devices, systems, and methods for multi-channel common-mode coupled alternating current (AC) gain amplifiers (MC-CM-AC Amp) are disclosed. The MC-CM-AC Amp can comprise a first operational amplifier including: a first non-inverting input port configured to be coupled to a first input signal, and a first inverting input port configured to be coupled to a first capacitor. The MC-CM-AC Amp can comprise a second operational amplifier including a second non-inverting input port configured to be coupled to a second input signal, and a second inverting input port configured to be coupled to a second capacitor. The MC-CM-AC Amp can comprise one or more gain-setting resistors configured to be coupled between the first capacitor and the second capacitor.

Abstract: The present application relates to the field of audio technology, and provides a method, a device, and an apparatus for playing audio, and a computer-readable storage medium. The method for playing audio includes: obtaining an ambient atmospheric pressure value and audio data to be played; obtaining multiple target frequency points contained in the audio data to be played when the ambient atmospheric pressure value meets a preset condition, and determining equal-loudness multiples corresponding to the target frequency points according to the ambient atmospheric pressure value and a preset calibration atmospheric pressure value; and sending the audio data to be played and the equal-loudness multiples of the target frequency points to a power amplifying module, such that the power amplifying module amplifies the audio data to be played according to the equal-loudness multiples corresponding to the target frequency points.