An amplitude detector using up-down counter

This article presents a novel and simple amplitude detector for sinusoidal signals. The realization technique utilizes up/down counting and holding capabilities of up-down counter without low-pass filter or sample-and-hold circuit requirement. The proposed circuit consists of a control signal generator, a peak detector, a windows detector, a digital-to-analog converter, and an up-down counter. The proposed detector can produce both analog output and 12-bit digital output signals, which are proportional to the amplitude value of analog input signals. In addition, output signals with small ripple can be achieved. The experimental results show that the proposed detector can work with the input voltage in range 250 mV to 5 V. The maximum frequency for input signals is approximately equal to 100 kHz with maximum analog output error of 0.8%. © 2012 ICIC International.