Class / Patent application number | Description | Number of patent applications / Date published |
330256000 | Having temperature compensation means | 7 |
20090115520 | Temperature compensation of collector-voltage control RF amplifiers - A temperature compensation system for compensating a collector-voltage controlled RF amplifier. To overcome variation that occurs with temperature which can result in signal degradation of the adjacent channel spectrum, a temperature compensated current is utilized to create an offset signal. The offset signal is processed in connection with a control or data signal to generate a temperature compensated voltage source control signal. A differential amplifier may process the data or control signal and the offset signal. The compensated voltage control signal tracks temperature to adapt the applied collector voltage to temperature. This in turn forces the applied collector voltage to vary in response to temperature changes thereby maintaining a constant output power or RF swing. One example environment of use is in an EDGE type GSM system. | 05-07-2009 |
20140167849 | DIFFERENTIAL AMPLIFIER - A differential amplification circuit includes a first current control unit configured to control driving current in response to a voltage level difference between first input voltage and second input voltage, a second current control unit configured to control the driving current in response to a voltage level difference between the second input voltage independent from temperature and a temperature voltage depending on the temperature, and a signal output unit configured to generate a detection signal in response to the driving current. | 06-19-2014 |
20140327482 | RADIO FREQUENCY POWER AMPLIFIER WITH NO REFERENCE VOLTAGE FOR BIASING AND ELECTRONIC SYSTEM - A radio frequency (RF) power amplifier with no reference voltage for biasing is disclosed. The RF power amplifier includes a three-terminal current source circuit, a current mirror circuit and an output-stage circuit. The three-terminal current source circuit receives a first system voltage and accordingly outputs a first current and a second current, and a source voltage exists between a first output terminal of the first current and a second output terminal of the second current. The current mirror circuit receives the first current and the second current and accordingly generates a bias current. The output-stage circuit receives the bias current so as to work at an operation point. The RF power amplifier utilizes the source voltage of the three-terminal current source circuit so the first system voltage is between a first voltage and a second voltage, and then the output-stage circuit outputs an output current which does not vary with a deviation of the first system voltage also with temperature compensation. | 11-06-2014 |
20150340998 | DIFFERENTIAL AMPLIFIER - A differential amplification circuit includes a first current control unit configured to control driving current in response to a voltage level difference between first input voltage and second input voltage, a second current control unit configured to control the driving current in response to a voltage level difference between the second input voltage independent from temperature and a temperature voltage depending on the temperature, and a signal output unit configured to generate a detection signal in response to the driving current. | 11-26-2015 |
20160072444 | COMPLEMENTARY METAL OXIDE SEMICONDUCTOR RADIO FREQUENCY POWER AMPLIFIERS WITH HIGH LINEARITY ACROSS A WIDE RANGE OF BURST SIGNALS IN WIFI APPLICATIONS - An RF power amplifier biasing circuit has a start ramp signal input, a main current source input, an auxiliary current source input, and a circuit output. A ramp-up capacitor is connected to the auxiliary current source input. A ramp-up switch transistor is connected to the start ramp signal input and is selectively thereby to connect the auxiliary current source input to the ramp-up capacitor. A buffer stage has an input connected to the ramp-up capacitor and an output connected to the main current source input at a sum node. A minor transistor has a gate terminal corresponding to the circuit output and a source terminal connected to the sum node and to the gate terminal. | 03-10-2016 |
20160079931 | DIFFERENTIAL TWO-STAGE AMPLIFIER AND OPERATION METHOD THEREOF - A differential two-stage amplifier is provided. The differential two-stage amplifier includes an input circuit, a bias circuit, a common mode feedback circuit, a first stage amplifier, a second stage amplifier and a current compensation circuit. The input circuit receives an input current. The bias circuit provides a bias current. The first stage amplifier is coupled to the input circuit and the second stage amplifier. The common mode feedback circuit is coupled to the second stage amplifier and adjusts a common mode feedback current according to a common mode voltage, wherein the input current is made up of the bias current and the common mode feedback current. The current compensation circuit provides a compensation current, wherein when a temperature of the differential two-stage amplifier is greater than a predetermined temperature, the compensation current is input to the input circuit. | 03-17-2016 |
20160134247 | AUTO-ZERO CIRCUIT OF OPERATIONAL AMPLIFIER - An auto-zero circuit of an operational amplifier is disclosed, and the auto-zero circuit has: a micro-control unit and a digital potentiometer; the micro-control unit is used to obtain a voltage value of an offset voltage of the output end when there is no input in the operational amplifier, and generates a control signal which causes the voltage value of the offset voltage to be smaller than a first threshold value according to the voltage value of the offset voltage; the digital potentiometer is used to adjust a resistance thereof according to the control signal. | 05-12-2016 |