LED LAMP WITH ADJUSTABLE ILLUMINATION INTENSITY BASED ON AC VOLTAGE AMPLITUDE

摘要

An LED lamp with adjustable illumination intensity is disclosed. The LED lamp comprises an illumination block having first, second, and third illumination modules, and first and second switches. The first, second, and third illumination modules are coupled in series between a rectification voltage node and a third connection node. The first switch selectively connects a first connection node shared by the first and second illumination modules to a basis voltage node. The second switch selectively connects a second connection node shared by the second and third illumination modules to the basis voltage node. The third connection node is coupled to the basis voltage node. A control block provides the first and second control signals respectively controlling the first and second switches, wherein the logic states of the first and second control signals are based on the amplitude of a driving voltage measured between the rectification and basis voltage nodes.