Tool/software:
Hi,
We are seeing an issue in our design where we are unable to drive any outputs of the DRV8245 (hardware variant).
The startup sequence is:
1. Put device into sleep mode by pulling nSleep low for >tSleep max
2. Wake up device by setting nSleep high for >tReady
3. Clear fault by pulling nSleep low for >tReset max (and less than tSleep min)
4. nSleep high
During the startup sequence we can see that nFault goes high when issuing the clear fault pulse, but about ~200us after the nFault goes low again.
We have multiple DRV8245 connected to the same nFault pin with a 10k ohm 3v3 pullup.
We have multiple DRV8245 connected to the same nSleep pin with a 10k pulldown.
Mode = Independent (8k2 ohm to GND)
IPROPI = 2k2 ohm to GND + 100nF in parallel.
ITRIP = 8k2 to GND
SR = 8k2 to GND
Diag = GND
DRVOFF is also tied to GND.
VM = 24V
We have tested with and without a load connected (low-side) but the outputs are not driven by the IN1/IN2 and the nFault is held low by the DRV8245.
Is it ok to tie the nFault outputs of multiple DRV8245 together?
Are there some issues with our setup that is not supported by the DRV8245?
Any ideas on where to look?