An analog-to-digital converter with time-variant window

We present a first order analog-to-digital converter with time-variant window. If a DC input is applied, the converter outputs a binary sequence until the internal state enters into the window. It is clarified analytically that the converter can realize higher resolution and lower error variation with shorter code length than previous converters. We also present a simple implementation method using a continuous-time circuit, where the digital output is represented by an impulse-train.