Patent ID: 7545137

Claim:
A current detecting circuit for testing a current flowing through a load, comprising: a current detecting module comprising a detecting resistor, the current detecting module configured to transform the current of the detecting resistor to an output voltage; a voltage transmitting module configured to receive the output voltage from the current detecting module, and send the output voltage to a read chip, the read chip reading the output voltage; and a current adjusting module comprising: a first field effect transistor (FET), wherein the drain of the first FET is connected to a power source via the detecting resistor; the source of the first FET is connected to the load; a second FET, wherein the drain of the second FET is connected to the gate of the first FET; the gate of the second FET is connected to a signal control pin of a pulse generator chip; a third FET, wherein the gate of the third FET is connected to the drain of the second FET; a fourth FET, wherein the gate of the fourth FET is connected to the drain of the third FET; the drain of the fourth FET is connected to the drain of the first FET; a first transistor comprising a base, a collector, and an emitter, wherein the source of the fourth FET is connected to the power source via a first resistor, and connected to the collector of the first transistor; a first operational amplifier, wherein a first non-inverting input terminal of the first operational amplifier is connected to the voltage transmitting module; an input pin of the read chip is connected to a first inverting input terminal of the first operational amplifier and a first output terminal of the first operational amplifier; the emitter of the first transistor is connected to a second inverting input terminal of the first operational amplifier, and ground via a second resistor; the base of the first transistor is connected to a second output terminal of the first operational amplifier; a voltage terminal of the first operational amplifier is connected to a first standby power source; and a voltage regulator diode, wherein the second non-inverting input terminal of the first operational amplifier is connected to the cathode of the voltage regulator diode and a first standby power source; the anode of the voltage regulator diode is grounded.