Method and apparatus for detecting differential threshold levels while compensating for baseline wander
AssigneeIntel Corporation
InventorMel Bazes
Life of this patent
Estimating the term…
Abstract
A method and an apparatus for detecting differential threshold levels of a differential signal being carried in first and second lines while compensating for baseline wander. In one embodiment, first and second single-ended signals and a common mode signal are generated in response to the first and second lines. First and second peak signals are then generated in response to the first and second single-ended signals and the common mode signal. Finally, first and second threshold signals are generated which are compared with the first and second single-ended signals to generate first and second output signals indicating first and second differential threshold levels.
Claims30
A sensing circuit for detecting differential threshold levels of a differential signal being carried in first and second lines, comprising:
- a first peak detector circuit coupled to the first and second lines, the first peak detector circuit detecting first and second peak voltages in the differential signal and generating first and second peak signals;
- and,
- a resistor network/comparator circuit coupled to the first and second lines and the first and second peak signals, the resistor network/comparator circuit generating a first output signal indicating a first differential threshold level of the differential signal;
- wherein the differential signal transitions between N different voltage levels wherein N is an integer greater than one, the resistor network/comparator circuit generating N-1 output signals, each one of the N-1 output signals corresponding to a differential threshold level between two of the N different voltage levels.
A sensing circuit for detecting differential threshold levels of a differential signal being carried in first and second lines, comprising:
- a first peak detector circuit coupled to the first and second lines, the first peak detector circuit detecting first and second peak voltages in the differential signal and generating first and second peak signals;
- a resistor network/comparator circuit coupled to the first and second lines and the first and second peak signals, the resistor network/comparator circuit generating a first output signal indicating a first differential threshold level of the differential signal;
- and
- a second peak detector circuit coupled to the first and second lines, the second peak detector circuit detecting third and fourth peak voltages in the differential signal and generating third and fourth peak signals, the resistor network/comparator circuit further coupled to the third and fourth peak signals.
A sensing circuit for detecting differential threshold levels of a differential signal being carried in first and second lines, comprising:
- a first peak detector circuit coupled to the first and second lines, the first peak detector circuit detecting first and second peak voltages in the differential signal and generating first and second peak signals;
- a resistor network/comparator circuit coupled to the first and second lines and the first and second peak signals, the resistor network/comparator circuit generating a first output signal indicating a first differential threshold level of the differential signal;
- wherein the first peak detector circuit comprises:
- a charge/discharge circuit coupled to the first and second lines;
- a first capacitor charged by the charge/discharge circuit to the first peak voltage, the first peak voltage being approximately equal to a peak positive voltage of the first line;
- and,
- a second capacitor discharged by the charge/discharge circuit to the second peak voltage in the differential signal, the second peak voltage being approximately equal to a peak negative voltage of the second line.
A method for detecting differential threshold levels of a differential signal being carried in first and second lines, comprising the steps of:
- detecting first and second peak positive voltages of the differential signal;
- detecting first and second peak negative voltages of the differential signal;
- generating a positive differential threshold output signal in response to the first and second lines, the first and second peak positive voltages and the first and second peak negative voltages;
- and,
- generating a negative differential threshold output signal in response to the first and second lines, the first and second peak positive voltages and the first and second peak negative voltages.
A sensing circuit for detecting differential threshold levels of a differential signal being carried in first and second lines, comprising:
- a converter circuit coupled to the first and second lines, the converter circuit generating first and second single-ended signals and a common mode signal;
- a first peak detector circuit coupled to the first single-ended signal and the common mode signal, the first peak detector circuit generating a first peak signal;
- a second peak detector circuit coupled to the second single-ended signal and the common mode signal, the second peak detector circuit generating a second peak signal;
- and,
- a comparing circuit coupled to the first and second single-ended signals, the first and second peak signals and the common mode signal, the comparing circuit generating a first output signal indicating a first differential threshold level of the differential signal.
A method for detecting differential threshold levels of a differential signal being carried in first and second lines, comprising the steps of:
- generating first and second single-ended signals in response to the first and second lines;
- generating a common mode signal in response to the first and second lines;
- detecting a first peak signal in response to the first single-ended signal and the common mode signal;
- detecting a second peak signal in response to the second single-ended signal and the common mode signal;
- generating a first output signal indicating a first differential threshold level of the differential signal in response to the first single-ended signal, the first and second peak signals and the common mode signal;
- and,
- generating a second output signal indicating a second differential threshold level of the differential signal in response to the second single-ended signal, the first and second peak signals and the common mode signal.
Dependencies are inferred from the claim text.