Flicker in LED Floor Lamps: Reading the Driver Before the Wattage
Two LED floor lamps with identical wattage can behave very differently on camera and to sensitive users, and the cause sits in the driver rather than the LED board. This article outlines what to check on a driver specification and how to test a sample quickly.
LED sources respond to current almost instantaneously, which means any ripple left by the driver appears directly as light modulation. Whether that modulation is visible depends on its depth and frequency, and both are properties of the driver output stage rather than of the LED board itself.
For residential floor lamps the practical consequences are two. Under a phone camera a modulated source produces banding across the frame, which customers read as a defect even when the light looks steady to the eye. In reading and task positions, sustained modulation is a comfort complaint that tends to appear in reviews rather than in returns.
A driver specification worth requesting states the output ripple at rated load, the dimming method and the usable dimming range. Dimming is where flicker usually appears: a driver that is stable at full output can begin to modulate at the low end of a phase-cut or pulse-width dimming curve.
A quick bench check does not require laboratory equipment. Pointing a phone camera at the lamp through its dimming range and watching for moving bands catches the worst cases, and comparing two samples side by side on the same dimmer is more informative than reading the numbers separately.
For buyers building a private-label range, the useful step is to fix the driver requirement in the specification rather than to approve a finished sample. The LED board, the diffuser and the mechanical parts can change between orders; the ripple behaviour follows whichever driver is fitted, so it should be named.