A high-speed signal detection method and circuit

Abstract

The invention provides a high-speed signal detection circuit and a method. The high-speed signal detection circuit comprises a signal operation moding circuit, a comparison circuit, a current source, another comparison circuit and a low-pass filter. The method comprises the steps of firstly, inputting a differential data signal into the signal operation circuit for processing the signal; secondly, comparing processed voltage signals by two voltage comparison circuits; thirdly, processing a comparison result by the low-pass filter; fourthly, processing the above filtered signal via a two-input NAND gate to obtain the validity of the signal. According to the technical scheme of the invention, the circuit is simple in structure and high in reliability, which can be widely applied to the validity detection of signals in Ethernet buses and the like.

Description

technical field [0001] The invention belongs to the electronic circuit design technology, and relates to a high-speed signal detection method and a circuit. The invention can be used in high speed bus receiver applications. Background technique [0002] Signal detection technology is widely used in various high-speed bus interfaces, such as Ethernet, 1394 and PCIe. During the transmission process of various buses, it is necessary to negotiate the rate, negotiate the port characteristics, judge whether the bus is idle, whether the signal of the bus is a valid signal, etc. These functions are all realized by the signal detection circuit. [0003] Usually, a sample-and-hold circuit is used in a signal detection circuit to sample the signal, and then compare it with a reference voltage. The sample-and-hold circuit is generally composed of an operational amplifier and a common-mode bias circuit. The reference voltage is generated by an independent reference voltage module, and ...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the technical problems of limited detection rate, large power consumption and large area in the existing signal detection circuit, the present invention provides a high-speed signal detection circuit and method. The method adopts the current mode working mode to improve the signal detection speed. The input signal is converted from a voltage signal to a current signal. In order to detect the validity of the input signal, it is necessary to judge whether the signal amplitude reaches the reference current. The reference current is calculated in the current mode and the positive and negative terminals of the differential signal converted into the current mode in the current mode. After the calculation Four sets of current signals are obtained, which are the current value of the positive terminal of the differential signal, the current value of the negative terminal of the differential signal, the current value of the positive terminal of the differential signal minus the reference current, and the current of the negative terminal of the differential signal minus the reference current value, and then convert these four sets of current signals into voltage signals and output them to two comparators. The two comparators compare the output voltage signals in pairs. The signal is input to the two-input NAND gate for processing. When the output of the NAND gate is low, it means that the received signal is valid. When the output of the NAND gate is high, it means that the received signal is invalid.

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