Hello All,
I'm putting together a motor controller board using the DRV8825 IC and having some issues with power on. I'm measuring 12.2V at the input cap C5 as well as on C1, C3 and C4, but the internal regulator V3P3OUT does not produce anything. None of the IC pins are shorted and no motor is connected to VMA and VMB pins. nReset and nSleep pins are tied to VP3OUT via 10K pull-ups and the enable pin is floating. Per the data sheet, this configuration should enable the IC.
Attached my schematic and board layout (2 layer with solid GND on bottom). The IC was purchased from DigiKey and should be good.
I know that the calculation for Vref is now slightly off because I designed it for 12V not 12.2V but my understanding it is that if it affects anything that would be the current limitation.
Is there anything that stands out as an issue with the schematic, or board layout that would cause this?