Patent attributes
A ballast-bypass light-emitting diode (LED) tube lamp includes at least a first and second external connection terminal, the first and second external connection terminals respectively connected to opposite sides of the ballast by-pass LED tube lamp. The tube lamp includes an LED module, configured to emit light in response to a driving current, and a power supply module, electrically connected to the first and second external connection terminals for receiving an AC driving signal and configured to provide the driving current to the LED module. The power supply module comprises a rectifying circuit, a filtering circuit, a driving circuit, and a circuit electrically connected to the driving circuit and configured to operate in response to whether a foreign external impedance is connected to the LED tube lamp. When part of the LED tube lamp is electrically connected to an external power source and the foreign external impedance is electrically connected to the LED tube lamp, the first circuit disables the driving circuit so as to limit the generation of the driving current to prevent the LED module from emitting light based on the driving current. When both ends of the LED tube lamp are electrically connected to an external power source and the foreign external impedance is not electrically connected to the LED tube lamp, the first circuit enables the driving circuit so as to not limit the generation of the driving current in order to allow the LED module to emitting light based on the driving current.
