带失调自校准的MIPI D-PHY高速通道设计

Design of MIPI D⁃PHY High⁃speed Channel with Offset Self⁃calibration

基于移动产业处理器接口(Mobile Industry Processor Interface,MIPI)协议提出了一种应用于显示驱动芯片数据接口的物理层电路。针对数据传输对速度要求越来越高的情况以及失调电压会使输出信号的占空比偏离50%,进而影响高速采样准确率的问题,采用多级放大器形式实现了高速通道设计,并利用可编程电流源进行失调电压的自适应校准,减小了失调电压在传输中带来的误差。电路使用SMIC 110 nm CMOS工艺进行设计。仿真结果表明,自适应校准可以使-30 mV~35 mV的输入失调电压降低到-1 mV~1.2 mV,单通道传输速率达到1.5 Gbps,实现了高速、高精度的数据传输效果。

A physical layer circuit applied to the data interface of display driver chips was pro-posed based on Mobile Industry Processor Interface(MIPI)protocol.In response to the increasing speed requirements for data transmission and the issue of offset voltage causing the duty cycle of the output signal to deviate by 50%,which affected the accuracy of high-speed sampling,a multi-stage amplifier structure was adopted to achieve high-speed channels and programmable current source was used for adaptive calibration of offset voltage,reducing the error caused by offset voltage in transmis-sion.The circuit was designed using SMIC 110 nm CMOS technology.The results of post simulation showed that adaptive calibration could reduce the input offset voltage of-30 mV~35 mV to-1 mV~1.2 mV,and the transmission rate of single channel could reach 1.5 Gbps,achieving high-speed and high-precision data transmission.