The motors we choose are 6V nominal but the documentation says they can be driven with 9V. The stall current is of 360mA.
I choose a driver IC we had on our mentor graphics library, the L6206. I have one uncertainty about it, it’s its over current protection. The datasheet gives information on how to calibrate the current threshold using a resistance between 5k and 40k. The problem is that the minimum threshold previewed (with a 40k resistance) is about 552 mA, which is above the stall current. I am not sure this is a big problem, if anyone has comments I’d appreciate =].
Meanwhile I am searching a voltage regulator for the motor. It has to generate the 9V with 800mA, from the voltage coming from the battery/usb system. This input voltage is not constant and may vary from 2.5 to 4.2 V. Looking for some options at Linear technologies, I found some ICs, and narrowing down to the simpler and most adapted ones I got these:
None are available in our library, so one of them needs to be added. I could not see important differences between them, but I think the 1872 is a little more powerful than we need. For now I am going with the 1370.
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