Hi,
I tried to run a steppermotor with torque on, so that the motor locks the rotor and you cannot move it by hand between steps.
After a short while the L6219 driver got VERY hot. It’s seems reasonable that it should, but the trimmer that controls output current is just halfway turned up.
Question is, how hot is too hot for this driver? I don’t want this driver to go up in smoke to tell me I’m doing something wrong.
Any suggestions?
Greetz, Deekay
Please check the datasheet, they mention max. operating temperatures for different conditions.
Checked out the datasheet for the L6219 from ST, this tells me that the driver has a maximum Junction Temperature of 150 Degrees C! (Thermal shutdown at 170 C).
I also checked the schematics of the K8097 and found that I01 , I02 , I11, and I12 which control the current-ratio for coils 1 and 2 from the motor are connected to the controller. The current can be controlled by logic and set to: 1/3, 2/3 or Full current. The datasheet is not clear about if this logic setting is in respect to the level set with the trimmer but I do know that the controller always sets this to maximum current.
I would like to try the different current settings because my stepper-motors do not require holding torque, since they drive threaded shafts and therefore don’t need to hold weight. However if I don’t use holding torque, the motor keeps losing steps here and there.
I am not really comfortable with the maximum current setting which the controller now sets for the holding torque, as this will generate A LOT of (unnecessary) heat in the drivers and probably shorten their life a lot quicker.
In my humble opinion this should be made selectable as well as an option for Half step motor-drive.
I know that the board as it is now, has some great potential but is let down by firmware and as such feels incomplete.
Is there an update planned for this board that addresses these issues?
Sorry, not at this time.
If you are capable, we can provide the firmware so that you can tweak it, but we need you to understand that we can only supply it ‘as-is’ and in no way we can assist with modifications or questions regarding the firmware.
Yes please,if it is newer than the one I got earlier(V0.1) but I have a some questions about that.
Is the program on the PIC protected because I want to make a backup of the original HEX in there. If it is protected, I will order a blank one and start from there.
If I solder a ICSP header on the board, will it work with ICD2/3 or PIC-KIT? I also have an external programmer available (Advantech Labtool 48 UXP) but that’s not my first choice because that one is at my professional workplace and it’s impossible to take it home; we use it on a daily basis.
Would you like me to publish my result back to you?