Voltage fluctuations caused by rapidly changing loads in the power systems may give rise to noticeable illumination flickers of lighting equipment. The voltage flickers can also cause malfunctions in many electric devices. This paper presents a digital implementation of flickermeter in the hybrid time and frequency domains based on IEC standard 61000-4-15. In addition, this paper proposes a new demodulation method to extract the voltage envelope. Simulations and actual measurements show that the digital implementation with the proposed method yields relatively accurate flicker measurements.