|
Match
|
Document |
Document Title |
|
|
7626456 |
Overdrive control system
An overdrive control system includes a voltage controlled current source to deliver a compensation current, and being between a first voltage reference and an internal node, which is connected to...
|
|
|
7619481 |
Circuit for inhibiting over-current in power amplifier
A power amplifier drives a load connected to a first output terminal and a second output terminal. When generation of over-current is detected by the current detection section, the output amplifier...
|
|
|
7595696 |
Power amplifier
A power amplifier including an active device having at least one heterjunction bipolar transistor based on a compound semiconductor; a diode connected between the base and the emitter of the...
|
|
|
7586369 |
Pulse modulation type electric power amplifier
A pulse modulation type electric power amplifier includes a pulse modulator that receives as input a clock and an input signal, and converts the input signal to a pulse train, an output control...
|
|
|
7551034 |
Saturation handling
Saturation handling for preventing a power amplifier from going into a saturation condition is disclosed.
|
|
|
7525389 |
Signal amplifier circuit with a limiting voltage device
A signal amplifier circuit includes a negative feedback amplifier circuit having an output terminal, a first voltage limiting device for limiting the output voltage from the negative feedback...
|
|
|
7489199 |
Saturation detector and warning circuit including clamp
A saturation detection and warning circuit having an adaptive threshold voltage is disclosed. The disclosed circuit can also be used to detect the impending drop out of the low drop out linear...
|
|
|
7482877 |
Power protecting apparatus and method for power amplifier
A power protecting apparatus and method of a power amplifier for removing backward voltages and preventing a hard damage within a circuit by connecting an output terminal of a DC-DC converter with...
|
|
|
7477107 |
Protection circuit and method for RF power amplifiers in WLAN transceivers
A protection circuit for a power amplifier of a radio frequency transmitter includes a sensing circuit that generates a sensed signal based on an output of the power amplifier. A reference signal...
|
|
|
7459979 |
Semiconductor indicator for voltage diagnostics in power amplifiers
A semiconductor indicator for quantitatively diagnosing voltage conditions in high power transistor devices is provided. The semiconductor indicator includes a first transistor and a second...
|
|
|
7449959 |
Methods and apparatus to detect impedance at an amplifier output
Methods and apparatus to detect impedance at an amplifier output are described. In one example, a method of determining a relative value of an amplifier output load may include determining a...
|
|
|
7394312 |
Re-configurable amplifier protection apparatus and method
The present invention is directed to an amplifier, which is able to re-configure its internal protection circuits based on an output signal level. This allows the amplifier to apply the best...
|
|
|
7391267 |
Output circuit
A patterning area of an output circuit is reduced while securing strong enough ESD tolerance. In the output circuit of this invention, an output of a first amplifier and an output of a second...
|
|
|
7375589 |
Power amplifier system provided with improved protection function
The present invention provides a power amplifier system that includes a power terminal, a ground terminal, an output terminal, a ripple terminal, a control terminal, a power amplifier circuit...
|
|
|
7362871 |
Audio amplifier circuit and audio IC having the same
In the present invention, in parallel with a resistor which determines an amplification rate being fed back from an output to an input of an output stage OP amp in an audio amplifier circuit,...
|
|
|
7352240 |
Method and apparatus for protecting devices in an RF power amplifier
A method and apparatus are provided for use with a power amplifier for protecting active devices on the power amplifier. A peak detector is used by control circuitry to detect the presence of a...
|
|
|
7339424 |
Apparatus and method for controlling temperature of electronic apparatus
In an embodiment of this invention, if a state, in which duty ratio of a PWM signal is kept equal to or greater than a predetermined value, has been maintained for a first time period, the duty...
|
|
|
7332969 |
Output offset protection for power amplifier
A output offset protection circuit provides protection of the load and the power amplifier through monitoring the temperature of the power transistor in the operational amplifier to detect fault...
|
|
|
7330072 |
Circuit for power amplification
A radio frequency (RF) power amplifier, including an external control loop and a protection circuit, which functions to maintain a constant output power during variations in impedance on the RF...
|
|
|
7327187 |
Method, circuit and power amplifier for detecting a fault, and method of protecting a circuit in a power amplifier from a fault occurrence
In a method of detecting a fault in a class D amplifier, an amplifier output signal is generated based on inverting a pulse width modulation signal corresponding to received audio data. The...
|
|
|
7298852 |
Dynamic power sharing in a multi-channel sound system
A signal processing system for use in a multichannel audio system. The signal processing system includes a first channel having a first audio signal. A second channel is included that has at least...
|
|
|
7282997 |
Thermal coupling device
A micro-electronic power amplifier that defines a uniform thermal impedance includes an output stage including a single transistor array including a plurality of emitter leads and a single thermal...
|
|
|
7276974 |
Method and apparatus for protecting RF power amplifiers
Method and apparatus are provided for protecting radio frequency (RF) power amplifiers. A circuit ( 10 ) is provided for limiting a supply current to a first stage (Q 3 ) of the RF power amplifier...
|
|
|
7262667 |
Radio frequency power amplifier
A radio frequency (RF) power amplification circuit including a power amplifier is provided for preventing breakdown of the power amplifier. The power amplifier includes an input for receiving RF...
|
|
|
7259618 |
Systems and methods for load detection and correction in a digital amplifier
Systems and methods for detecting the impedance of an output load coupled to a digital amplifier and compensating for changes in the response of the amplifier. One embodiment of the invention is...
|
|
|
7205840 |
Wideband CMOS gain stage
A CMOS gain stage includes biasing circuitry configured to insure saturation of a subsequent stage without a source follower circuit. The CMOS gain stage is optionally powered by a supply voltage...
|
|
|
7205834 |
Power amplifier
In a power amplifier driven by a pulse width modulation (PWM) signal, a first pair of drive pulses opposite in level to each other is formed from a first pulse width modulation signal whose...
|
|
|
7145396 |
Method and apparatus for protecting devices in an RF power amplifier
A method and apparatus are provided for use with a power amplifier for protecting active devices on the power amplifier. A peak detector is used by control circuitry to detect the presence of a...
|
|
|
7138864 |
Overcurrent protection in amplifier topologies employing DC isolation
An amplifier having output switch circuitry is described. A sense resistor is operable to transmit an output current associated with the output switch circuitry. Low-voltage circuitry is operable...
|
|
|
7102445 |
Power amplifier module
An amplifier 2 c amplifies a transmit signal and outputs the amplified transmit signal to an antenna 10 . A drive current for driving the amplifier 2 c is inputted to a drive current input...
|
|
|
7075373 |
Overcurrent protection circuit with fast current limiting control
An overcurrent protection circuit for a power transistor includes a transconductance amplifier and a bias current circuit. The transconductance amplifier receives a first signal indicative of the...
|
|
|
7071776 |
Systems and methods for controlling output power in a communication device
A mismatch detector including a directional device adapted to couple signals across the device and a detector coupled to a port on the directional device and configured to measure a reflected power...
|
|
|
7005924 |
Current limiting circuit with rapid response feedback loop
The current limiting circuit of the present invention includes a transconductance amplifier having two outputs and forming a conventional feedback loop. A first output connects to an output...
|
|
|
6980058 |
Amplifier circuitry
Input signal amplified by an input amplifier is delivered via a voltage limiter circuit to a power amplifier, and a speaker is driven by the signal amplifier by the power amplifier. Voltage...
|
|
|
6954104 |
Method and system for monitoring a deliverable radio frequency power of an amplifier operable on a monolithic microwave integrated circuit
A method and system are described for monitoring a deliverable radio frequency (RF) power of an amplifier operable on a monolithic microwave integrated circuit (MMIC). According to an exemplary...
|
|
|
6949977 |
Circuit arrangement having a transimpedance amplifier connected to a current limiter circuit
A circuit arrangement is provided which has the advantage of limiting the magnitude of the current to a transimpedance amplifier (TIA) circuit or a current to voltage converter during an overdrive...
|
|
|
6943629 |
Transient protection circuit of Darlington amplifier
A protection circuit for Darlington amplifiers prevents destructive voltage overshoot conditions from occurring. The Darlington amplifier has a pair of transistors connected in a Darlington...
|
|
|
6927626 |
Thermal protection system for an output stage of an amplifier
Disclosed is a thermal protection circuit for an amplifier generating an amplified AC output signal. The thermal protection circuit may be powered by an amplifier power supply used to power the...
|
|
|
6850119 |
Power amplifier overload protection
The present invention relates to detecting overload conditions from within the bias circuitry for a multistage amplifier. Preferably, the overload condition is detected in the bias circuitry...
|
|
|
6825727 |
Radio frequency power transistor avalanche breakdown detection circuit and method therefor
An apparatus for detecting the onset of avalanche breakdown in a radio frequency bipolar power transistor is provided. The radio frequency bipolar power transistor includes a first transistor cell...
|
|
|
6798282 |
Method and system for transimpedance amplifiers with high current input while maintaining high transimpedance gain and bandwidth
Method and system for a diode shunting configuration wherein the configuration prevents a transimpedance amplifier from saturation while maintaining high transimpedance gain and bandwidth. In one...
|
|
|
6794930 |
Signal quality
The invention relates to a method for improving the quality of the output signal of especially an audio output stage, which comprises at least a modulator circuit, in such a manner that in...
|
|
|
6774726 |
Amplifier with a MOS output stage
An amplifier including first, second, and third series-connected stages, the third stage including a MOS output transistor having its source or drain forming an output terminal of the amplifier,...
|
|
|
6744310 |
Power amplifying device
A power amplifying device promptly detects an abnormal condition of a load and permits protection of an output without causing power loss. A test signal having a predetermined frequency and signal...
|
|
|
6734729 |
Closed loop power amplifier control
The invention includes an integrated circuit chip having a closed loop control module. The closed loop control module includes a power amplifier coupled to a feedback control circuit. The power...
|
|
|
6724254 |
Audio amplifier with output power limiter
The amplifier comprises a power suppl, a current sensing element for sensing a current in the current path of the power supply, a detecting circuit responsive to the current sensing element, and...
|
|
|
6720831 |
Power amplifier protection circuit
A power amplifier circuit comprises a sensing circuit and a processing circuit adapted to detect voltage peaks in an output of a power amplifier. If the voltage peak is above a predetermined...
|
|
|
6653899 |
Audio amplifier power and temperature controller having network detecting and associated methods
An audio amplifier power and temperature controller and associated method are provided which preferably includes a power receiving circuit for receiving power from a power source to an audio...
|
|
|
6642795 |
Fast recovery time precision amplifier
An amplifier with a electrically controllable gain and enhanced protection against an overload condition is disclosed. The amplifier contains a buffer amplifier configured to convert an input...
|
|
|
6636118 |
High-frequency power amplification module and radio communication device
In a high frequency power amplifier module of a multi-stage structure in which a plurality of heterojunction bipolar transistors (npn-type HBTs) are cascade-connected, a protection circuit in which...
|