Most LED lamp designs can be characterized by a diode-capacitor power supply feeding a constant current source. The diodes rectify the applied AC voltage, allowing it to charge the storage capacitor, whilst the LED elements draw constant current from the power supply that is related to the desired brightness.
In LEd loads the applied voltage and resulting current flow are not related by a simple linear relationship ie current flows from the applied voltage to the load only when the magnitude of the applied voltage exceeds the storage voltage on the power supply capacitor. The stored voltage on the power supply capacitor, in turn, depends on the current drawn by the LED elements themselves, which is a function of the LED brightness. The dimmer unit has to respond to these minute and plentiful, wave form shifts, hence the flickering of the lamp and an unstable dimming circuit.
In LEd loads the applied voltage and resulting current flow are not related by a simple linear relationship ie current flows from the applied voltage to the load only when the magnitude of the applied voltage exceeds the storage voltage on the power supply capacitor. The stored voltage on the power supply capacitor, in turn, depends on the current drawn by the LED elements themselves, which is a function of the LED brightness. The dimmer unit has to respond to these minute and plentiful, wave form shifts, hence the flickering of the lamp and an unstable dimming circuit.
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