Noise shaping can aid ADC architectures to achieve high resolution. A new technique to increase ADC resolution is presented in this paper. It is based on Nyquist-rate ADC architectures and uses delayed analog quantization error to implement noise shaping function. The new technique is implemented using two-step and SAR ADC respectively. When the noise shaping order is one and the Over-Sampling Rate (OSR) is only 8, the system based on 5-bit two-step ADC can achieve the SNDR of 62.5-dB, while the SNDR of the system based on 6-bit SAR ADC can obtain 59.6-dB. Actually, this new technique consumes tiny amount of extra power. Although the speed of the system is decreased slightly because of the small OSR, as the resolution is increased significantly. As a result, the Figure of Merit (FOM) of the overall ADC can be improved. © 2011 IEEE.