Speed Control problem with L6235 DIP

vkyadav · ‎2016-10-25

Posted on October 25, 2016 at 20:05

Hi All,

I want to make a BLDC motor driver board using

L6235N DIP

.

I wired all the components on the breadboard as per schematic diagram and component list is given in ST Application Note AN1625 page no. 35-37.

I am using PWM from MCU to control the speed of the BLDC motor(Max Speed 3000RPM). Now motor is running and break, Direction, Tacho all these features are working fine but I have a little problem to control the speed .

generally, when I set the PWM duty Cycle 0% Motor should be stop but still motor is running arround 350RPM. PWM output is connected with Vref pin no. 13 of L6235N. I am unable to control the speed less than 350RPM but more than 350RPM Speed control is working fine. When I connect the PIN no. 13 (Vref) to 0V(Signal Ground) nothing changed motor still running at 350RPM but it should be stopped. I am using all the components as per given Application note AN1625.

I am unable to find out the problem. Any help would be appreciated.

Thanks in advance,

Regards,

Vijay K Yadav

#l6235n

AT2 · ‎2024-04-30

Hello,

I have the same issue. Did you ever find a solution to this? I am connecting microcontroller PWM directly to the Vref pin. Are you adding any additional circuitry?