Cytron Balancing Robot

[redips_id]

Hi Cytron,

I have a picture and coding about Cytron balancing robot and decided to do it. The coding is too tough to me to understand, however I would like to start from hardware first. I see 2 units of LMC6064 (quad precision ampifier) used in the board, I wonder it is used to amplify sensors or motor voltage? Since your coding read the motor voltage left and right (left 1, left 2, right 1, right 2). I guess it is used for amplifying motor signal. If that true, what kind of connection is used? Whether [voltage follower-non inverting] or [non inverting-voltage follower]? *i'm totally guess

Hope Cytron can share it
Since the author for this project is Koh Wai Weng, maybe you can share with me and all the forum guys
We will appreciate it..

[waiweng83]

Hi, the LMC6064 is used as voltage buffer (AKA voltage follower) for the gyro, accelerometer and back EMF from the motor. This allows shorter sample and hold time of the ADC of the MCU. The reading of motor voltage is to read the back emf from the motor in order to estimate the motor speed.

BTW, I'm not Koh Wai Weng.

[redips_id]

Oh really, I'm sorry, huhu..
Thanks for the info..

[redips_id]

As I know the voltage buffer circuit don't have any resistor, what I see there have 4 set of connection involve with resistor, it is non-inverting voltage amplifier?

[waiweng83]

The resistor is just a voltage divider to step down the motor back emf voltage so that it's between 0 - 5V

[redips_id]

The Vref for ADC operation is refer to AVdd and Avss, can I know the AVdd is connect to +5V or 3.3V? refer to the 'system.h', the GYRO_SENSITIVITY is set at 4.095 = 3.3mV (I refer to Gyro datasheet), so AVdd = 3.3V right?

[waiweng83]

Good observation~! To be frank, I do not remember already
Anyway, the AVDD must be same voltage with VDD, so I think the whole system should be running at 3V3.

[redips_id]

Thanks, now I start get a big view

However I still have a question, hehe, about LMC6064 (Quad Precision Amp), if I replaced with LT1014 (also Quad Precision Amp) from Cytron, it will give the same value?