To provide a versatile LED drive circuit which can satisfy requirements for low cost and low power consumption and which perform drive control with high accuracy regardless of an ambient temperature, and to provide an imaging device using the circuit.

The LED drive circuit is provided with an NPN transistor Q1 whose on/off-state is controlled by a PWM drive signal, a PNP transistor Q3 whose on/off-state is controlled by the on/off-state of the NPN transistor Q1, an LED 3 one end of which is connected with a power supply Vcc through the PNP transistor Q3 and the other end of which is grounded through a resistor 2, an NPN transistor Q2 and a resistor 1 one end of which is connected with connecting ends of the NPN transistors Q1 and Q2 and the other end of which is grounded. The circuit is so constituted that the NPN transistor Q2 is turned into an on state, a voltage of the resistor 2 is increased, and the NPN transistor Q1 is turned into an off-state when the voltage of the resistor 2 exceeds a predetermined value.

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