Receiver with time-varying threshold voltage
First Claim
Patent Images
1. An apparatus, comprising:
- an input node to receive from a serial link a serial stream of data bits, the data bits having logical values, wherein a given logical value is within a corresponding bit-duration;
a threshold generator circuit to generate a time-varying threshold voltage during the bit-duration;
a slicer, coupled to the input node and the threshold generator circuit, to resolve the logical values from the serial stream of data bits based at least on the time-varying threshold voltage;
a register to store an activation bit; and
control logic, coupled to the register, to selectively enable or disable the time-varying threshold voltage based at least on the stored activation bit.
0 Assignments
0 Petitions
Accused Products
Abstract
A system for communicating information between circuits is described. A transmit circuit provides pulse-amplitude-modulation (PAM) signals via a communication channel to a receiver. A circuit in the receiver determines digital values from the received signals using a time-varying threshold voltage, which varies during the bit-time. This approach may compensate for inter-symbol interference (ISI) to increase the voltage and timing margins of the system.
14 Citations
22 Claims
-
1. An apparatus, comprising:
-
an input node to receive from a serial link a serial stream of data bits, the data bits having logical values, wherein a given logical value is within a corresponding bit-duration; a threshold generator circuit to generate a time-varying threshold voltage during the bit-duration; a slicer, coupled to the input node and the threshold generator circuit, to resolve the logical values from the serial stream of data bits based at least on the time-varying threshold voltage; a register to store an activation bit; and control logic, coupled to the register, to selectively enable or disable the time-varying threshold voltage based at least on the stored activation bit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
-
-
21. An apparatus, comprising:
-
an input node to receive a signal representing a series of logical values, wherein a given logical value is within a corresponding bit-duration; a threshold generator circuit to generate a time-varying threshold voltage during the bit-duration; and a decision circuit to determine the logical values from the received signal based at least on the time-varying threshold voltage, wherein the decision circuit includes two instances of; a difference circuit, coupled to the input node, to compare the received signal and a given time-varying threshold voltage in a pair of time-varying threshold voltages; an integrator circuit, coupled to the difference circuit, to integrate the comparison result of the received signal and the given time-varying threshold voltage; and a slicer, coupled the integrator circuit, to determine the logical values; and
wherein the decision circuit further comprises a feedback circuit that includes;a memory to store a digital value from an immediately preceding bit-duration; and a multiplexer, coupled to the memory and slicers in the first and second instances of the difference circuit, the integrator circuit, and the slicer, to select an output from one of the slicers during a current bit-duration based at least on the stored digital value in the memory. - View Dependent Claims (22)
-
Specification