Servo Analog control

[burningfire]

hi nerds 

for a class project I need to build a full analog circuit for controlling a servo motor (using dc motor and gearbox ... )  . I searched a bit and also read a previous topic of this forum  : https://www.eevblog.com/forum/chat/circuit-request-servo-motor-feedback-control-circuit/

I know about it's feedback loop and how to use potentiometer and op-amp in it but here is a question :

Do I still need PWM or square pulses in my Analog control ?
 since hobby servos have three wires : gnd - vcc - and another one for pwm pulses , I didn't know if how and why I should use it in my analog design .

[donotdespisethesnake]

hi nerds 
Do I still need PWM or square pulses in my Analog control ?
 since hobby servos have three wires : gnd - vcc - and another one for pwm pulses , I didn't know if how and why I should use it in my analog design .

No, but you need some way to direct the position of the servo. It could be an analog voltage in the range 0-10V for example. Hobby servos use pulse width modulation - the width of the pulse in time determines the position.

[Benta]

Search for "RC servo tester".