公开(公告)号：US09385740B2

公开(公告)日：2016-07-05

申请号：US14919830

申请日：2015-10-22

Applicant: MEDIATEK Inc.

Inventor： Chi Yun Wang ,  Jen-Che Tsai ,  Shu-Wei Chu

IPC: H03M1/38 ,  H03M1/46 ,  H03M1/42 ,  H03M1/12 ,  H03M1/08 ,  H03M1/40

CPC classification number: H03M1/462 ,  H03M1/0854 ,  H03M1/12 ,  H03M1/1245 ,  H03M1/38 ,  H03M1/403 ,  H03M1/42 ,  H03M1/466 ,  H03M1/468 ,  H03M3/37 ,  H03M3/458

Abstract: A SAR ADC including a comparator, an input switch unit, a positive conversion capacitor array, a negative conversion capacitor array, and a SAR controller is provided. The input switch unit alternately couples and decouples a differential analog input signal to the comparator. The positive and negative conversion capacitor arrays sample the differential analog input signal during the sampling phase. The SAR controller resets the switches in the capacitor arrays at the end of the sampling phase to change the sampled voltage into a residual signal, generates an intermediate digital code to control the switches during the conversion phase according to an output of the comparator to convert the residual signal to the intermediate digital code, generates the digital code according to the intermediate digital code, and uses an inverted intermediate digital code to control the switches at the end of the conversion phase.

Abstract translation: 提供了包括比较器，输入开关单元，正转换电容器阵列，负转换电容器阵列和SAR控制器的SAR ADC。 输入开关单元将差分模拟输入信号交替耦合到比较器。 正和负转换电容器阵列在采样阶段对差分模拟输入信号进行采样。 SAR控制器在采样阶段结束时复位电容器阵列中的开关，将采样电压改变为残余信号，产生一个中间数字代码，根据比较器的输出在转换阶段控制开关，以转换 到中间数字码的残留信号，根据中间数字码产生数字码，并在转换阶段结束时使用反相中间数字码来控制开关。