Hi,
Now we are testing circuit (DRV8412, circuit is very similar than in datasheet Figure 17)
(Please visit the site to view this file)
We have some problems with circuit,
10% pwm steps up or down are working.
20% pwm steps or more is not working, fault situation is occurred. I guess it was over current fault because only Fault LED went on.
Then we changed OC_ADJ to 23kohm and still same same fault occurs.
It's not clear that is driver working in CBC mode or OC mode.
Could you help with these issues? below you'll find the schematic, 2 TEC elements (CP40336) are connected in series to output of the driver.
Additionally when I am driving this bi-directional driver from cooling 10% --> heating 10%, is also not working (see picture below, ch3-4 output, ch2 PWM_A), but this is not causing fault.
ch3 is going low as it should be but then after ~15us it goes up, kind of floating.
-Mikko