Straight tube LED illumination lamp
This straight tube LED illumination lamp includes the following: an LED element; a first plug having an input-output terminal and an empty terminal; a second plug having an input-output terminal and an empty terminal; a first rectifier that is connected to the input-output terminal of the first plug and the empty terminal of the second plug in order to convert alternating current to direct current; a second rectifier that is connected to the input-output terminal of the second plug and the empty terminal of the first plug in order to convert alternating current to direct current; and a bypass circuit through which current is flown back from either the first or second rectifier to the other rectifier. The bypass circuit has a current-limiting resistor to prevent the first and second rectifiers from being damaged.
1. A straight tube LED illumination lamp, comprising:
LED elements;
a first plug having a first input-output terminal and a first empty terminal;
a second plug having a second input-output terminal and a second empty terminal;
a first rectifier, connected to the first input-output terminal of the first plug and the second empty terminal of the second plug to convert a first alternating current to a first direct current;
a second rectifier, connected to the second input-output terminal of the second plug and the first empty terminal of the first plug to convert a second alternating current to a second direct current; and
a bypass circuit, through which a current back is flown from one of the first rectifier and the second rectifier to the other one of the first rectifier and the second rectifier,
wherein the bypass circuit has a current-limit resistor to prevent the first and second rectifiers from being damaged.
2. The straight tube LED illumination lamp according to claim 1 , wherein the bypass circuit further comprises a switch in order to block the bypass circuit.
3. A straight tube LED illumination lamp, comprising:
LED elements;
a rectifier converting an alternating current to a direct current;
a switching element, arranged in series between the rectifier and the LED elements;
a detector detecting an actual direct current provided to the LED elements; and
a high frequency pulse generating device repeatedly switching on and off the switching element at a high frequency for maintaining the actual direct current to a set value,
wherein when the actual direct current exceeds the set value, the high frequency pulse generating device switches the switching element to an “OFF” state and maintains the switching element to off for a fixed “OFF” time.
4. The straight tube LED illumination lamp according to claim 3 , wherein the fixed OFF time is long enough to maintain the switching element to the “OFF” state, and short enough not to generate a flicker even though the actual direct current becomes lower than the set value.