Patent ID: 9325537
Filing Date: 2016-04-26
CPC Classification: H04L

Claim Text:
1. A method of closed loop compensation in a receiver including a decision feedback equalizer (DFE), the method comprising: detecting a composite data path gain of the receiver, the data path including a variable gain amplifier (VGA), a linear equalizer (LEQ) and the DFE; receiving a present decision from the data path at both a DFE tap adaptation circuitry and a VGA/LEO adaptation circuitry; based at least in part on the received present decision and further based on one or more past decisions of the data path, adaptively setting path gain, filter, and/or equalizer parameters with the DFE tap adaptation circuitry and VGA/LEQ adaptation circuitry; determining a position of a main cursor tap value of the DFE with respect to a target level to detect data path gain or attenuation; detecting effect of a process, voltage and temperature (PVT) condition based on the determined position of the main cursor tap value against a present value of gain of the VGA when the present value of gain of the VGA is at a lowest or highest gain setting; adjusting the data path gain or attenuation based on the detected PVT condition and the adaptively set path gain,filter, and/or equalizer parameters by adjusting a voltage regulator controlling the VGA gain; and adjusting the data path gain or attenuation based on the detected PVT condition and the adaptively set path gain, filter, and/or equalizer parameters by adjusting a differential pair gain of the LEQ and DFE data path.