10位高速分级比较型单斜模数转换器

A 10bit High Speed Two-levels Single-slope ADC

本文设计了一种用于CMOS图像传感器的高速列并行分级比较型单斜模数转换器。利用两个斜坡发生器,采取两次分区间比较和减法运算相结合的方式,将信号分级转换。结合流水线操作模式,转换速度比传统单斜模数转换器提高12倍。该ADC在0.18μm工艺下,实现了10位精度和263ks/s的高转换速度。ADC的DNL=+0.83/-0.82LSB,INL=+0.51/-1.5LSB,SNR=58.28dB,ENOB=9.3bit。

A design of highspeedcolumn parallel two-levels single-slope ADC for CMOS image sensor is presented.The signal is converted by two sub division and subtraction operation using two ramp generators.With the pipelined operation mode,the conversion speed is 12 times higher than that of the conventional single slope ADC.The ADC achieves 10 bit accuracy and 263ks/s high conversion rate with 0.18μm process.The DNL,INL,SNR,ENOB of the ADC are ＋0.83/-0.82 LSB,＋0.51/-1.5LSB,58.28 dB and 9.3bit respectively.