LED lamp and power source module thereof related applications
An LED lamp and a power source module thereof are provided. The power source module includes a switch-type DC-to-DC converter integrated with a function for detecting whether a foreign external impedance exists. The switch-type DC-to-DC converter is configured to enter an installation detection mode when the switch-type DC-to-DC converter is activated. When the switch-type DC-to-DC converter is in the installation detection mode, the switch-type DC-to-DC converter receives an external AC signal received by the LED lamp to detect whether a foreign external impedance exists based on the received signal.
1. An LED lamp, comprising:
a first pin and a second pin, configured to receive an external AC signal;
a light strip;
an LED module, comprising at least one LED mounted on the light strip; and
a power supply module, electrically connected to the LED module through the light strip and configured to drive the LED to emit light when the LED lamp is properly installed, wherein the power supply module comprises:
a rectifying circuit, having an input side electrically connected to the first pin and the second pin and having an output side, wherein a DC signal is observed at the output side of the rectifying circuit when the first pin and the second pin receive the external AC signal;
a filtering circuit, having an input side electrically connected to the output side of the rectifying circuit and having an output side; and
a switch-type DC-to-DC converter integrated with a function for detecting whether the LED lamp is properly installed, is electrically connected to the LED module and the output side of the filtering circuit, and is configured to enter an installation detection mode when the switch-type DC-to-DC converter is activated,
wherein when the switch-type DC-to-DC converter is in the installation detection mode, the switch-type DC-to-DC converter detects a signal at the input side of the rectifying circuit to determine whether the LED lamp is properly installed based on the detected signal,
wherein when the LED lamp is determined to be properly installed, the switch-type DC-to-DC converter enters a normal operating mode to provide an output power to drive the LED to emit light, and
wherein when the LED lamp is determined to be not properly installed, the switch-type DC-to-DC converter remains in the installation detection mode.
2. The LED lamp according to claim 1 , wherein when an additional 500 ohm resistor is electrically connected to the power supply module in series, the LED lamp is determined to be not properly installed.
3. The LED lamp according to claim 1 , wherein the power source module further comprises:
a first diode, having an anode electrically connected to the input side of the rectifying circuit;
a first resistor, having one end electrically connected to a cathode of the first diode and another end electrically connected to the switch-type DC-to-DC converter.
4. The LED lamp according to claim 3 , wherein the switch-type DC-to-DC converter comprises:
a pulse generating circuit, electrically connected to the other end of the first resistor and configured to trigger a pulse signal, having a pulse width between 1 microsecond and 100 microseconds, for detection based on the signal at the other end of the first resistor in the installation detection mode.
5. The LED lamp according to claim 3 , wherein the switch-type DC-to-DC converter comprises:
a detection path circuit, electrically connected to the other end of the first resistor and configured to conduct a pulse current, having a pulse width between 1 microsecond and 100 microseconds, passing through the first diode and the first resistor in the installation detection mode.
6. The LED lamp according to claim 1 , wherein the switch-type DC-to-DC converter is further configured to periodically trigger current pulses at a falling edge of the external AC signal in the installation detection mode.
7. The LED lamp according to claim 6 , wherein the switch-type DC-to-DC converter determines a time point for triggering each current pulse according to the external AC signal.
8. The LED lamp according to claim 7 , wherein the switch-type DC-to-DC converter triggers the current pulses when a voltage of the external AC signal drops to fall below a reference voltage level.
9. The LED lamp according to claim 7 , wherein the switch-type DC-to-DC converter triggers the current pulses when the external AC signal reaches a first phase angle.
10. The LED lamp according to claim 6 , wherein a pulse width of at least one of the current pulses is between 1 microsecond and 100 microseconds, and a time interval of at least two adjacent current pulses is between 3 milliseconds and 500 milliseconds.
11. The LED lamp according to claim 6 , wherein the switch-type DC-to-DC converter triggers a group of the current pulses comprising at least two current pulses for determining whether the LED lamp is properly installed before entering the normal operating mode.
12. A power source module adapted to drive an LED module, comprising:
a first circuit, having an input side for receiving an external AC signal and having an output side, wherein a DC signal is observed at the output side of the first circuit when the external AC signal is applied;
a first capacitor, electrically connected to the output side of the first circuit;
a first inductor, having one end electrically connected to one end of the first capacitor;
a second capacitor, having one end electrically connected to another end of the first inductor; and
a switch-type DC-to-DC converter integrated with a function for detecting whether a foreign external impedance exists, electrically connected to a connection node of the first inductor and the second capacitor through a bias resistor, and configured to enter an installation detection mode when the switch-type DC-to-DC converter is activated,
wherein when the switch-type DC-to-DC converter is in the installation detection mode, the switch-type DC-to-DC converter receives a signal at the input side of the first circuit to detect whether the foreign external impedance exists based on the received signal,
wherein when the foreign external impedance does not exist, the switch-type DC-to-DC converter enters a normal operating mode to provide an output power to drive the LED module, and
wherein when the foreign external impedance exists, the switch-type DC-to-DC converter remains in the installation detection mode.