Discrete-time dynamic compensation of analog-to-digital converters

The use of post-sampling digital signal processing to linearize the behavior of high speed flash analog-to-digital converters (ADCs) is discussed. Dynamic compensation of the sampled ADC input is achieved by accessing an error correction table using the current state of the converter and an estimate of the derivative of the input signal. A finite impulse response (FIR) filter is used to provide the estimate of the slope of the input signal, resulting in a compensation procedure which may be implemented for any off-the-shelf converter. Performance is shown to be comparable to that obtained using other procedures which require either modifications of the ADC architecture or the use of multiple ADCs