Patent ID: 7400188

Claim:
A voltage providing circuit for an electronic component, the voltage providing circuit comprising: a power supply circuit adapted for providing a voltage to the electronic component; and a first transistor, a first control signal being input to a collector of the first transistor, a second control signal being input to a base of the first transistor, an emitter of the first transistor grounded, the collector of the first transistor connected to the power supply circuit, and the second control signal and the first control signal jointly controlling the power supply circuit to be turned on or turned off, wherein the voltage providing circuit further comprises a second transistor and a third transistor, the second transistor and the third transistor are NPN transistors, the second control signal is input to a base of the second transistor, a collector of the second transistor is connected to a base of the third transistor, a collector of the third transistor is connected to the base of the first transistor, the second voltage is input to the collectors of the second transistor and the third transistor, and when the second control signal is at a high level, a voltage of the base of the first transistor is at a high level, wherein the voltage providing circuit further comprises a fourth transistor and a fifth transistor, the fourth transistor and the fifth transistor are NPN transistors, a third control signal is input to a base of the fourth transistor, a collector of the fourth transistor is connected to a base of the fifth transistor, a collector of the fifth transistor is connected to the base of the third transistor, the second voltage is input to the collectors of the fourth transistor and the fifth transistor, and when the third control signal is at a high level, a voltage of the base of the third transistor is at a high level.