hi,i just want to make an automatic fan controller,based on this circuit:
This project uses IC LM35 as a sensor for detecting accurate centigrade temperature. Output voltage of this sensor is linearly proportional to the Celsius (Centigrade) temperature. This sensor use the fact that, as temperature increases, the voltage across a diode increases at a known rate. Output of IC is 10mv/degree centigrade for eg if temperature is 45 degree then the output of sensor will be 450mv or 0.45V
Output data of sensor is applied to a current amplifier circuit and feed to a low power DC motor. We have made current amplifier by using a general purpose NPN transistor. I have used BC548 as shown in the circuit diagram
But my question is:How could i take the value of transistor parameters (R,I) to make this circuit working good?Thanks
This project uses IC LM35 as a sensor for detecting accurate centigrade temperature. Output voltage of this sensor is linearly proportional to the Celsius (Centigrade) temperature. This sensor use the fact that, as temperature increases, the voltage across a diode increases at a known rate. Output of IC is 10mv/degree centigrade for eg if temperature is 45 degree then the output of sensor will be 450mv or 0.45V
Output data of sensor is applied to a current amplifier circuit and feed to a low power DC motor. We have made current amplifier by using a general purpose NPN transistor. I have used BC548 as shown in the circuit diagram
But my question is:How could i take the value of transistor parameters (R,I) to make this circuit working good?Thanks