Abstract:
An analog baseband filter for a radio transceiver is provided. An analog baseband filter for a multi-mode multi-band radio transceiver includes a current-voltage conversion amplifier converting a current received at the analog baseband filter into a voltage and adjusting a gain of an output voltage of the current-voltage conversion amplifier using a plurality of resistors, and a source follower circuit compensating for temperature for the output voltage of the current-voltage conversion amplifier.
Abstract:
An analog amplifier for recovering an abnormal operation of a common-mode feedback is provided. An analog variable amplifier includes a first input transistor and a second input transistor, a first output transistor and a second output transistor, a third transistor and a fourth transistor, a first current source, a fifth transistor and a sixth transistor, and a second current source. The first input transistor and the second input transistor amplify a bias current depending on a magnitude of a first input voltage and a second input voltage. The first output transistor and the second output transistor output the amplified bias current. The third transistor and the fourth transistor receive an output voltage of the first output transistor as an input and amplifying the received output voltage. The first current source provides a predetermined current between the first output transistor and the third transistor.
Abstract:
An analog baseband filter for a radio transceiver is provided. An analog baseband filter for a multi-mode multi-band radio transceiver includes a current-voltage conversion amplifier converting a current received at the analog baseband filter into a voltage and adjusting a gain of an output voltage of the current-voltage conversion amplifier using a plurality of resistors, and a source follower circuit compensating for temperature for the output voltage of the current-voltage conversion amplifier.
Abstract:
Provided is a method and apparatus for controlling home devices forming a home network at a time by using a mobile terminal in a home network system. In particular, the present disclosure provides a method and apparatus for controlling home devices at a time, depending on a type of contents. A method for playing contents in a Home GateWay (HGW) in a home network system includes receiving from a mobile terminal a control command requesting continuous playback of contents that are currently played in the mobile terminal and controlling at least one home devices in response to the control command.
Abstract:
An apparatus and a method for exponentially controlling a gain of a driver amplifier to drive a power amplifier are provided. The driver amplifier includes a plurality of cascode amplifier segments, wherein when a plurality of candidate gain values of the driver amplifier is arranged, the candidate gain values form a geometric sequence. A unit cost can be reduced by halving an area occupied by the driver amplifier.
Abstract:
A semiconductor device is provided that includes a first chip that generates a single signal by connecting a first signal line and a second signal line, to which differential signals are respectively provided, and outputs the single signal to a third signal line. The first chip is driven by a first power supply voltage. The semiconductor device also includes a second chip comprising an analog-to-digital converter (ADC) that receives the single signal through the third signal line, compares the single signal with a reference voltage, and outputs a digital signal based on the comparison. The semiconductor device also includes a controller that monitors the digital signal and adjusts the reference voltage to be approximately equivalent to the first power supply voltage.
Abstract:
An analog amplifier is provided. The analog variable amplifier includes a first amplifier stage configured to amplify a bias current to output a first output voltage and a second output voltage that respectively depend on a magnitude of a first input voltage and a second input voltage, a second amplifier stage configured to receive the first output voltage and the second output voltage of the first amplifier stage as inputs and to amplify the received first output voltage and the second output voltage, and at least one auxiliary bias current source coupled to an electrical connection between the first amplifier stage and the second amplifier stage through which the second amplifier stage receives the first output voltage, and coupled to an electrical connection between the first amplifier stage and the second amplifier stage through which the second amplifier stage receives the second output voltage.
Abstract:
An analog baseband filter apparatus for a multi-mode and multi-band wireless transceiver and a method for controlling the analog baseband filter apparatus are provided. The analog baseband filter apparatus includes a plurality of Radio Frequency (RF) units, each of the plurality of RF units being for receiving RF signals of one of a plurality of frequency bands and outputting baseband signals, a plurality of filter blocks for filtering and amplifying the baseband signals, and a switching unit for connecting at least two of the plurality of RF units to at least one of the plurality of filter blocks according to a selected communication mode, wherein the at least one of the plurality of filter blocks is configured to be connected to a capacitor region of an adjacent filter block from among the plurality of filter blocks.
Abstract:
A variable gain amplifier circuit is provided. The circuit includes an operational amplifier for amplifying and outputting an input signal according to a cutoff frequency and a gain, a feedback resistor for changing a first resistance according to a first digital control code value which determines the cutoff frequency, and an input resistor for changing a second resistance according to a second digital control code value which is determined based on a difference of the first digital control code value and a gain code value. The gain is determined by a ratio of the first resistance and the second resistance and linearly changes on a decibel (dB) basis according to the first digital control code value, the cutoff frequency is inversely proportional to the first resistance and linearly changes on a log scale, and the variable gain can be easily set using the control code.
Abstract:
An Analog-Digital Converter (ADC) is provided. The ADC includes a plurality of sigma-delta modulators, a plurality of decimators, a plurality of differentiators, and a plurality of XOR operators. The plurality of sigma-delta modulators respectively convert analog signals to digital pulses. The plurality of decimators respectively convert a first sampling rate of a corresponding digital pulse to a second sampling rate which is lower than the first sampling. The plurality of differentiators respectively differentiate signals converted at the second sampling rate to perform delta modulation. The plurality of XOR operators extract a signal component changing with respect to the delta-modulated signals. Therefore, the number of interface pins between a modem and an RFIC can be reduced.