数字控制PFC中3路8bits时分复用SAR ADC的设计

A 3-channel 8-bit Time-Division Multiplexing SAR ADC for Digital PFC Controllers

本文设计了3通道8bits时分复用SAR ADC,采用电荷再分配方法实现8位DAC,自校准比较器降低比较器的偏移误差。所设计的模数转换器采样频率1.6MHz,输入电压范围为0-3.3V。该设计在Chartered 0.18μm工艺中实现,后仿真表明,当以1.6MHz采样频率采样30k Hz正弦输入信号时,INL和DNL分别在-1.00LSB/+1.11LSB和-0.72LSB/+0.95LSB内。

In this paper,a 3-channel 8-bit time-division multiplexing SAR ADC is designedCharge redistribution method is employed to realize an 8-bit DAC.To reduce the offset error of comparator,a self-calibrating comparator is adopted.The proposed ADC has a 1.6MHz sampling frequency and an input voltage range from 0 to 3.3V.The design is implemented in a Chartered 0.18μm process.The post-simulation shows that INL and DNL are within-1.00LSB/+1.11LSB and-0.72LSB/+0.95LSB respectively,when sampling 30kHz sinusoid input signal at 1.6MHz sampling frequency.