Abstract:
There is provided a circuit and method for providing a supply voltage to an operational amplifier. A switch has a plurality of inputs connected to a respective plurality of supply voltages. An output of the switch is connected to a supply voltage terminal of an operational amplifier. The input of the switch is selected in dependence of the voltage levels to which a signal is to be amplified
Abstract:
The present invention relates to a transceiver for bidirectional frequency division multiplexed transmission. The transceiver comprises transmission means with a voltage source output or a current source output for transmitting data in a transmission frequency range, receiving means for receiving data in a receiving frequency range, and a coupling impedance for connecting the transmission means and the receiving means to a transmission medium. The magnitude of the coupling impedance in the transmission frequency range is smaller than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a voltage source output and is higher than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a current source output. Due to the reduced magnitude or increased magnitude respectively in the transmitting frequency range, the transmit signal power requirement is reduced.
Abstract:
The present invention relates to a transceiver for bidirectional frequency division multiplexed transmission, a communication system including one or more transceivers. Optionally, the communication system is a communication system for a digital subscriber line. The transceiver comprises transmission means with a voltage source output or a current source output for transmitting data in a transmission frequency range, receiving means for receiving data in a receiving frequency range, and a coupling impedance for connecting the transmission means and the receiving means to a transmission medium. The magnitude of the coupling impedance in the transmission frequency range is smaller than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a voltage source output and is higher than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a current source output. Due to the reduced magnitude or increased magnitude respectively in the transmitting frequency range, the transmit signal power requirement is reduced. In one variant of the invention, the magnitude of the coupling impedance is matched to the magnitude of the impedance of the transmission medium in order to increase the power of the received signals.
Abstract:
The present invention relates to a hybrid circuit for bidirectional communication over a communication line, the hybrid circuit directing a transmit signal inputted at an input line to the communication line and directing a receive signal received on the communication line to an output line different to the input line, the input line and the output line being coupled with a primary side of a transformer, the secondary side of the transformer being coupled with the communication line. Optionally, the hybrid circuit can be used within a communication system for a digital subscriber line. The primary side of the transformer comprises two coils with a first terminal and a second terminal respectively, the coils being connected in series via a middle impedance arranged between the first terminals of the coils. The input line is coupled with the second terminals of the coils, wherein a first output terminal of the output line is connected via a first impedance to a first terminal of the input line and via a second impedance to the first terminal of the second coil and a second terminal of the output line is connected via a third impedance to the second terminal of the input line and via a fourth impedance to the first terminal of the first coil. With this configuration the number of required components can be reduced which is a cost and size advantage. Furthermore the present invention has the advantage to reduce the attenuation of the receive signal in the hybrid circuit.
Abstract:
The present invention relates to a transceiver for bidirectional frequency division multiplexed transmission, a communication system including one or more transceivers. Optionally, the communication system is a communication system for a digital subscriber line. The transceiver comprises transmission means with a voltage source output or a current source output for transmitting data in a transmission frequency range, receiving means for receiving data in a receiving frequency range, and a coupling impedance for connecting the transmission means and the receiving means to a transmission medium. The magnitude of the coupling impedance in the transmission frequency range is smaller than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a voltage source output and is higher than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a current source output. Due to the reduced magnitude or increased magnitude respectively in the transmitting frequency range, the transmit signal power requirement is reduced. In one variant of the invention, the magnitude of the coupling impedance is matched to the magnitude of the impedance of the transmission medium in order to increase the power of the received signals.
Abstract:
The present invention relates to a transceiver for bidirectional frequency division multiplexed transmission, a communication system including one or more transceivers. Optionally, the communication system is a communication system for a digital subscriber line. The transceiver comprises transmission means with a voltage source output or a current source output for transmitting data in a transmission frequency range, receiving means for receiving data in a receiving frequency range, and a coupling impedance for connecting the transmission means and the receiving means to a transmission medium. The magnitude of the coupling impedance in the transmission frequency range is smaller than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a voltage source output and is higher than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a current source output. Due to the reduced magnitude or increased magnitude respectively in the transmitting frequency range, the transmit signal power requirement is reduced. In one variant of the invention, the magnitude of the coupling impedance is matched to the magnitude of the impedance of the transmission medium in order to increase the power of the received signals.
Abstract:
There is provided a circuit and method for providing a supply voltage to an operational amplifier. A switch has a plurality of inputs connected to a respective plurality of supply voltages. An output of the switch is connected to a supply voltage terminal of an operational amplifier. The input of the switch is selected in dependence of the voltage levels to which a signal is to be amplified.
Abstract:
There is provided a circuit and method for providing a supply voltage to an operational amplifier. A switch has a plurality of inputs connected to a respective plurality of supply voltages. An output of the switch is connected to a supply voltage terminal of an operational amplifier. The input of the switch is selected in dependence of the voltage levels to which a signal is to be amplified.
Abstract:
The invention refers to an electronic system, comprising several power-dissipating components, and a circuit board, wherein said power-dissipating components are mounted both to a top side and a bottom side of said circuit board. Further, the invention refers to method for mounting power-dissipating components onto a circuit board, comprising the steps of (a) determining the thermal behavior of said power-dissipating components; and (b) determining, in accordance thereto, the placement of said power-dissipating components on both a top side and a bottom side of said circuit board.
Abstract:
The present invention relates to a transceiver for bidirectional frequency division multiplexed transmission, a communication system including one or more transceivers. Optionally, the communication system is a communication system for a digital subscriber line. The transceiver comprises transmission means with a voltage source output or a current source output for transmitting data in a transmission frequency range, receiving means for receiving data in a receiving frequency range, and a coupling impedance for connecting the transmission means and the receiving means to a transmission medium. The magnitude of the coupling impedance in the transmission frequency range is smaller than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a voltage source output and is higher than the magnitude of the coupling impedance in the receiving frequency range if the transmission means has a current source output.