Abstract: A self-adjusting window circuit suitable for fabrication as a monolithic integrated circuit. The self-adjusting window circuit comprises an input port, a positive edge detector coupled to the input port, a latch coupled to the output of the edge detector and a charging stage coupled to the latch. The input signal comprises a signal having a sequence of pulses appearing at a predetermined scan rate, for example, a composite video signal. The input port feeds the input signal to the edge detector which produces a pulse output signal in response to detecting a pulse in the input signal. The pulse output from the edge detector is latched and used to generate a charging control signal which controls the charging stage. In response to the charging control signal, the charging stage produces a window control signal for a predetermined period.