From the PTS:
Required Shutdown Sequence
Warning: To avoid causing issues with the file system, follow this shutdown sequence.
- Drive Full_Card_Power_Off# low.
- Wait for at least t_pwr_off_seq seconds.
- Remove power.
t_pwr_off_seq is 25 seconds.
This is a completely new requirement in Revision 7 of the PTS - Rev. 6 stated:
Full_Card_Power_Off# (Pin 6) - Powers the module on/off.
• Signal is required.
• Pull HIGH to keep the module on. To keep the module
· Tie the pin directly to a host GPIO (1.8V), or
· Use an external pull-up to pull signal high (10k–20k
for 1.8V, 75–100k for VCC rail). Note that a larger-
value resistor will reduce leakage current.
Drive LOW to turn the module off.
There is no required shutdown sequence in Rev. 6, keeping Pin 6 high is explicitly allowed …