If at any time the voltage on the VCP pin falls below the CPUV voltage:
All the outputs are disabled (High-Z)
nFAULT pin is driven low
The charge pump remains active
For the SPI version, the FAULT and CPUV bits are made 1b
Normal operation resumes (motor-driver operation and nFAULT released) when the VCP undervoltage condition is removed. The CPUV bit remains at 1b until it is cleared through the CLR_FLT bit or an nSLEEP reset pulse.