Led drive circuit
AssigneeMurata Manufacturing Co., Ltd.
InventorYumin SAIGO
Life of this patent
Estimating the term…
Abstract
An LED drive circuit includes a power supply terminal, an LED, a first switch, and a first resistor are connected in series. The power supply terminal, a third resistor, and a second switch are connected in series. A connection point between the third resistor and the second switch, and a control terminal of the first switch are connected. A second resistor is connected between a connection point between the first switch and the first resistor, and a control terminal of the second switch. A first PTC thermistor is connected to a connection point between the control terminal of the second switch and the second resistor.
Claims13
An LED drive circuit comprising:
- a power supply terminal;
- p1 an LED;
- a first switch;
- a second switch;
- a first resistor;
- a second resistor;
- and
- a third resistor;
- wherein
- the power supply terminal, the LED, the first switch, and the first resistor are connected in series;
- the power supply terminal, the third resistor, and the second switch are connected in series;
- a connection point between the third resistor and the second switch, and a control terminal of the first switch are connected;
- the second resistor is connected between a connection point between the first switch and the first resistor, and a control terminal of the second switch;
- and
- a first PTC thermistor, or a second PTC thermistor and an NTC thermistor connected in series with each other are connected to a connection point between the control terminal of the second switch and the second resistor.
Dependencies are inferred from the claim text.