First of all, thank you for spending time replying our questions.
(1) What we gonna do:
We have a project on controlling a electronic throttle in a car. The EV(electronic throttle) needs 12V PWM signal(600 Hz, current: at least 1A). Now, we choose Baby Orangutan B-328 as our controller, which is already having an H-bridge embedded on the board supplying 1A continous current. We use the M1B (Timer 0 PWM output B) and M1A(Timer 0 PWM output A) to control the “Motor +” and “Motor -” of the EV.
When we try to control the EV with our scheme, we find the H-bridge on the B-328 is getting hot and the power supply(supplying 12V to B-328) turns to be short circuit. We wonder that B-328 only provides 5V PWM signal which is insufficient to drive the EV. Therefore, we want to ask for your kind help. Can we just use some simple BJTs or MOSFETs to solve this problem? Or are there still something wrong with our scheme?
Thank you again for your replies .
by James and Bruce
Hello, James and Bruce.
The motor driver on the Baby Orangutan is powered by the supply voltage, so if you are powering the Baby Orangutan with 12V, the PWM signal from the motor outs should go up to 12V. You should not need to add transistors to boost the signal.
Could you tell us more about the electronic throttle? Does it accept frequencies over 600Hz? Could you provide a link to its specifications and datasheet?
This sounds like it can potentially be a dangerous project. Please note that we do not recommend using our products for applications where failure can cause personal injury.
Thank you for your reply.
The ET(electronic throttle) that we used is 91 88 186 of Saab company, which is driven by a DC brushless motor with 12V/5A rating. The ET is controlled by 600Hz PWM signal ( It is OK that we used Arduino Uno with 490 Hz PWM signal).
After rechecking the specs, we find that the problem is caused by the insufficient current supplies. The Baby O- tries its best to supply the maximum current to the motor, which makes the H-bridge extremely hot!
So, can we use some circuits to boost the current to 5A?
Thank you for your answers!
by James and Bruce
The motor driver on the Baby Orangutan is for brushed DC motors; not brushless DC motors. Although it might be possible to control a brushless motor with the Baby Orangutan, I recommend switching to a driver that was designed for brushless motors. Unfortunately, we do not have any controllers for brushless motors.