I am working in a project in which I am controlling a NEMA17 stepper driver, controlled with a DRV8825. Due to my velocity needs, I am supplying 41.5V to the drivers approximately (it comes from a battery so the voltage level can change).
When running my system, everything works correctly, but when the driver reaches a certain temperature, the overheating system turns off and on the driver since the temperature reached is above the limits. This makes clear that my system needs some kind of dissipation.
In order to test the consumption of each of the motors, I have measured the current provided by the power supply to the drivers. I measured 0.15A, so a total of 6.2W are being provided to the driver.
On the other side, if I measure the voltage and current on the motor’s phases, I obtained that for each phase, 1.5W are being provided to the motor (2V x0.75A), so a total of 3W (1.5Wx2) are being supplied to the motors. Subtracting this to the total power given by the power supply, I realized that approximately 3.2W are being dissipated by the driver as heat power.
I was wondering whether it would be a better option to locate a heatsink on the top of the driver or on its bottom, since there’s a metallic plate where thermal vias are located. I couldn’t find out if there’s an optimal place to locate it since I could get the thermal information of the chip but not from the carrier, so I don’t know if more heat is being dissipated from the top or from the bottom.
Thank you all.