LED lamp circuit
Provided is an LED lamp circuit, comprising an LED luminous component circuit, a rectifier circuit, and an output control circuit coupled between the LED luminous component circuit and the rectifier circuit. The LED luminous component circuit comprises at least one light-emitting diode. The rectifier circuit is configured to output a rectified voltage to the LED luminous component circuit. The output control circuit comprises a voltage regulator circuit and a control switch circuit. The voltage regulator circuit comprises a thermosensitive device and a voltage divider connected in series. The thermosensitive device can regulate the control voltage at both ends of the control switch circuit. To protect the LED lamp, the control switch circuit disconnects when the control voltage is less than the threshold voltage of the control switch circuit.
1. A LED lamp circuit comprising:
an LED luminous component circuit comprising at least one LED;
a rectifying circuit configured to produce a rectified voltage output to the LED luminous component circuit;
an output control circuit coupled between the LED luminous component circuit and the rectifying circuit, the output control circuit comprising a voltage regulation circuit and a control switch, the voltage regulator circuit being connected in parallel with the rectifying circuit, the voltage regulator circuit being separate from the control switch, the voltage regulation circuit comprising a thermosensitive component and a voltage dividing component connected in series, the thermosensitive component configured to regulate a control voltage of the control switch, and wherein the control switch disconnects when the control voltage is lower than a threshold voltage of the control switch, the thermosensitive component comprising a plurality of thermistors connected in parallel, each thermistor of the plurality of thermistors having respective first and second ends, the respective first ends of each of the plurality of thermistors being coupled to the voltage dividing component and the respective second ends of each of the plurality of thermistors being coupled to the rectifying circuit.
2. The LED lamp circuit of claim 1 , wherein the control switch is coupled between the voltage regulator circuit and the LED luminous component circuit.
3. The LED lamp circuit of claim 1 , wherein a total number of pins of the lamp circuit is equal to a total number of thermistors of the plurality of thermistors.
4. The LED lamp circuit of claim 1 , wherein the voltage dividing component comprises a voltage dividing resistor.
5. The LED lamp circuit of claim 1 , wherein the voltage dividing component comprises a voltage regulation tube.
6. The LED lamp circuit of claim 1 , wherein the control switch comprises a field-effect transistor, the field-effect transistor comprises a gate, a source and a drain, and the gate of the field-effect transistor is coupled between the thermosensitive component and the voltage dividing component.
7. The LED lamp circuit of claim 6 , wherein the plurality of thermistors comprises at least one negative temperature coefficient thermistor, the source of the field-effect transistor is coupled to one end of the at least one negative temperature coefficient thermistor, the gate of the field-effect transistor is coupled between the at least one negative temperature coefficient thermistor and the voltage dividing component, the drain of the field-effect transistor is coupled to the LED luminous component circuit.
8. The LED lamp circuit of claim 7 , wherein the at least one negative temperature coefficient thermistor comprises four negative temperature coefficient thermistors connected in parallel.
9. The LED lamp circuit of claim 6 , wherein the rectifying circuit receives input voltage via at least two input pins and the plurality of thermistors comprises a positive temperature coefficient thermistor associated with each of the input pins, each thermistor connected in parallel, the source of the field-effect transistor is coupled to one end of the voltage dividing component, the gate of the field-effect transistor is coupled between the voltage dividing component and the at least one positive temperature coefficient thermistor, the drain of the field-effect transistor is coupled to the LED luminous component circuit.
10. The LED lamp circuit of claim 9 , wherein the at least one positive temperature coefficient thermistor comprises four positive temperature coefficient thermistors connected in series.
11. A lamp, comprising:
at least two input pins electrically coupled to a ballast;
a rectifying circuit electrically coupled to the at least two input pins and configured to produce a rectified voltage output to a light emitting diode (LED) component;
an output control circuit coupled between the LED component and the rectifying circuit, the output control circuit comprising a voltage regulation circuit and a control switch, the voltage regulator circuit being connected in parallel with the rectifying circuit, the voltage regulator circuit being separate from the control switch, the voltage regulation circuit comprising a thermosensitive component including a plurality of thermistors connected in parallel and being associated with each of the at least two input pins, each thermistor connected in parallel, and a voltage dividing component connected in series, the thermosensitive component configured to regulate a control voltage of the control switch, and wherein the control switch disconnects when the control voltage is lower than a threshold voltage of the control switch, each thermistor of the plurality of thermistors having respective first and second ends, the respective first ends of each of the plurality of thermistors being coupled to the voltage dividing component and the respective second ends of each of the plurality of thermistors being coupled to the rectifying circuit.