hi if i send analog output from arduino to the base of transistor( that iam using it as a switch)
do i get speed controlling by this analog output a the base ?.
note:npn BJT
Provided you use an appropriate base resistor, the transistor has enough gain to
drive the load and you take precautions if the load is inductive (which I presume it
is - a motor?)
Details of the load and power supply would be useful - every transistor has its limits
so its important to check you have an adequate device for the job.
voltage source at the collector with the ground connected to the emmiter ground i want to send analog to pnp's transistor base to move in the region of active forward to saturation in order to get a speed changing
npn or pnp? You've apparently changed your mind.
By analog output you mean PWM yes?
that iam using it as a switch
move in the region of active forward to saturation
My understanding is that to use a transistor as a switch, it must act like a switch i.e. either on or off. Applying a voltage to the base that results in a base current less than what is required for saturation will not accomplish that. The common method is to use PWM to turn the transistor on (saturation) and off (open circuit) at different durations of the high and low portions of the PWM signal to regulate the motor's speed. - Scotty