Temperature of easydriver

In the first post, I didnt put heatsink on the easydriver, the temperature of IC is very hot, by putting extra heatsink, it help to cool down a bit. In order to hold the heatsink tight to IC, I put some thermal paste in between and after it dry, it is holding good.

I use two different heatsinks to cover the stepper driver IC.

For this easydriver, I use the normal surface mounted type heatsink. The size nicely matched.

For this one, I am using the TO220 heatsink, a little oversize, but the IC is well-covered.

Size comparison between two heatsinks are shown as follow, a dip 8 socket is put as benchmark.

The heat distribution of both easydrivers are as follow.

The temperature of surface mounted heatsink is much higher than the TO-220 heatsink. I took a closer picture on the first driver, the temperature is 107 Celsius (figure below).

For the second driver, it has much lower temperature and much better heat dissipation. The jumper wire blocking the thermal sensing. Anyway the hottest part is 85 Celsius.

I only left the easydriver on for 3 minutes and look at the temperature.

Imagine the temperature of easydriver without heatsink and you run it for half an hour.
So heatsink is crucial from stepper motor driver as it has low efficiency.

The selection rule for heatsink is the bigger, the better.