Abstract: A circuit comprises an amplifier circuit and a trimming circuit. The amplifier circuit includes an operational amplifier. The operational amplifier has a first input configured to receive input signals, and the operational amplifier also has a second input and an amplifier output. One of the first input or the second input is a negative input. The trimming circuit is coupled to the amplifier output. The trimming circuit includes a termination resistor coupled in parallel with at least one trimming resistor. The termination resistor is coupled to a first switch in series, and the trimming resistor is coupled to a second switch in series. The amplifier output is connected back to the negative input through the first switch.

Abstract: A line driver for a communications system requiring multiple power sources for different modes of operation comprises a current source and a voltage source coupled in parallel with the current source. The current source has a first terminal and a second terminal. The line driver further comprises a first source resistor coupled to the first terminal of the current source and a second source resistor coupled to the second terminal of the current source. The current source provides a driving current and the voltage source provides a driving voltage at the same time during operations of the communications system.

Abstract: A data communication system comprising a first transmitter set configured to transmit a first output based on a first signal, the first output including one of a training pattern and a first data, the training pattern and the first data including clock information, a second transmitter set configured to transmit a second output based on the first signal, the second output including one of the training pattern and a second data, a first receiver set configured to generate a first received data based on the first output, a second receiver set configured to generate a second received data based on the second output, a clock and data recovery (CDR) circuit configured to extract the clock information based on the first signal and the first received data and provide a second signal indicating whether a frequency in-lock status is reached, a phase control circuit in the second receiver set, the phase control circuit being configured to detect a phase difference between the first received data and the second received

Abstract: A data communication system comprising a first transmitter set configured to transmit a first output based on a first signal, the first output including one of a training pattern and a first data, the training pattern and the first data including clock information, a second transmitter set configured to transmit a second output based on the first signal, the second output including one of the training pattern and a second data, a first receiver set configured to generate a first received data based on the first output, a second receiver set configured to generate a second received data based on the second output, a clock and data recovery (CDR) circuit configured to extract the clock information based on the first signal and the first received data and provide a second signal indicating whether a frequency in-lock status is reached, a phase control circuit in the second receiver set, the phase control circuit being configured to detect a phase difference between the first received data and the second received

Abstract: A circuit capable of quiescent current control, the circuit comprising a first operational transconductance amplifier (OTA) including a first output terminal, a first transistor including a first gate coupled to the first output terminal of the first OTA, a second OTA including a second output terminal, a second transistor including a second gate coupled to the second output terminal of the second OTA, a resistive load including a first terminal coupled to the first output terminal and the first gate, and a second terminal coupled to the second terminal and the second gate, a first current source capable of providing a first current flowing toward the first terminal of the resistive load, and a second current source capable of providing a second current flowing away from the second terminal of the resistive load.

Abstract: A circuit capable of quiescent current control, the circuit comprising a first operational transconductance amplifier (OTA) including a first output terminal, a first transistor including a first gate coupled to the first output terminal of the first OTA, a second OTA including a second output terminal, a second transistor including a second gate coupled to the second output terminal of the second OTA, a resistive load including a first terminal coupled to the first output terminal and the first gate, and a second terminal coupled to the second terminal and the second gate, a first current source capable of providing a first current flowing toward the first terminal of the resistive load, and a second current source capable of providing a second current flowing away from the second terminal of the resistive load.