Design Of Adaptive Low Power Adjustable Current Source

In the modern life and production, electronic technology has become an indispensable part of life in all fields of production. The current source used as a driving device is indispensable in a wide variety of electronic circuit. In addition to the constant and precision, now power consumption is one of the main design index of the current source. With the process feature size decreasing, the transistor integration increases rapidly. With the integration increasing, the heat emitted by the circuit per unit area increase correspondingly. And the speed of the heat growth is far greater than the growth speed of the heat dissipation capability of the circuit. But the high power consumption will make the transistor out of the normal ambient temperature range. The lifetime of transistor will be deteriorated. In severe cases, even the transistor will be failure. But if we pay much attention on the heat dissipation performance of current source, we must increase the heat radiation module. And the volume of current source will increase.At the same time, when we are on the constant pursuit of the stability and precision of current source, we must solve the heat dissipation caused by the excessive power consumption. And it is also very important to reduce the volume of the current source.The acquisition of current source transistor voltage at both ends is used as the feedback signal in this design. The optocoupler feedback to the switching power supply control chip is used to control the switching power supply output voltage. Through the control of switching power supply output voltage and ensuring the current source output current to control the triode voltage at both ends and reduce the current source power consumption, which will reduce the fever and the volume of current source. We conduct simulation on the designed circuit and analyze the simulation result. It turns out each part of the circuit can meet the design requirements. The designed circuit is realized by the hardware. The experiment is conducted and it verifies the correctness of designed circuit and the good effect of reducing power consumption.