Pre-emphasis circuit with configurable emphasis intensity

• Main Authors: CHEN NUXING, BAI CHUANG, SHI DAYONG, MA ZHUO, FANG LIANG, ZHAO ZHENYU, TANG LIHONG, LI SHAOQING, CHEN JIHUA, ZHANG MINXUAN, JIANG RENJIE, WANG YONGWEN, XIAO HAIPENG, XU WEIXIA
• Format: Patent
• Language: Chinese; English
• Published: 04.11.2009
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; PULSE TECHNIQUE

The invention discloses a pre-emphasis circuit with configurable emphasis intensity for high-speed I/O interfaces. The pre-emphasis circuit comprises a regulation circuit and an emphasis circuit, wherein the core of the regulation circuit is a delay unit variable in time delay, and the emphasis circuit comprises a fast charge-discharge unit and a four-pipe logic inverter. The regulation circuit receives a full-width random data signal and a feedback low-swing-amplitude output data signal, and generates two paths of pulse control signals adjustable in pulse width according to different input selection signals. When different inputs jump, the emphasis circuit determines the time to fast charge or discharge an output node according to the pulse width of the two paths of control signals generated by the regulation circuit so as to realize pre-emphasis effects different in intensity, and simultaneously limits output swing amplitude through self-feedback so as to realize output signals high in speed and low in swin