An adaptive algorithm for reconfigurable analog-to-digital converters

Abstract

Wireless portable device is desired to efficiently manage its power consumption in order to prolong its battery life. By dynamic monitoring, power utilization can be adjusted according to different signal behaviors and operation modes. This paper proposes a new adaptive algorithm for reconfigurable analog-to-digital converters (ReADC). Reconfiguration of analog-to-digital converter (ADC) is achieved by exploiting switching activity of its digital outputs and adjusts its resolution via an adaptive digital controller unit. The converter increases its resolution when the digital output changes is high and reduces its resolution when signal variation is low. MATLAB simulation results show that the algorithm is real-time adaptive and suitable for typical converter types implementation. Depending on different signal scenarios, average resolution of ReADC is lower than a fixed operation ADC. As approximation, power model for ReADC is presented to estimate ReADC power consumption especially for pipeline implementation. When implemented as adaptive control unit (ACU) for reconfigurable pipeline ADC, only 40 percent of power is used when operates with minimum 4-bit compared to conventional 10-bit ADC. Over entire signal duration, this power saving approach is capable of saving power up to 50 percent of total ADC power usage.