Lsi Corporation

Agere Systems Inc.

Avago Technologies General IP (Singapore) Pte. Ltd.

Shu Dong Cheng

Ming Chen

Yan Xu

Jun Tian

Donghui Wang

Hao Chen

Dong Hui Wang

Zhengxin Cao

De Qun Ma

A method for offset cancellation in a receiver loss of signal (RxLOS) circuit of a serializer/deserializer (SerDes) receiver device includes receiving a differential input signal via the first stage of a peak detector cell of the RxLOS circuit and shorting the differential output of the first stage via a control switch of the second stage of the RxLOS circuit. The control switch may further transition the RxLOS circuit from normal operating mode to an offset cancellation mode wherein the control switch may manually or automatically short the differential output of the first stage.

Simplified and effective offset calibration circuit for RxLOS in serdes

Described embodiments include a level shifter that provides a voltage level shift to applied signals, the amount of voltage shift being accurately controlled and independent of PVT. The level shifter has first transistor configured as a voltage follower with the gate coupled to an input terminal of the shifter and the source coupled to a node, a diode-connected transistor coupled between the node and an output terminal of the circuit, a first controlled current source coupled to the node, and a second controlled current source coupled to the output terminal. A controller receives a bandgap-stabilized voltage, squares the stabilized voltage to produce a control signal that controls the first and second controlled current sources. The voltage shift is proportional to a digitally-controlled scale factor (K) times the stabilized voltage. The ratio of the current from the first current source to the second current source is (K+1)/K.

Adjustable level shifter

Various embodiments of the present invention provide systems and methods for signal offset cancellation. For example, a method for error cancellation is disclosed. The method includes: receiving an input signal that includes a second order error component; applying a transfer function to the processed input to reduce the second order error component; and providing an output signal that is the result of applying the transfer function to the input signal.

Systems and methods for high order asymmetry correction

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Shanghai, China

Shu Dong Cheng