uMMC Timing Characteristics

Parameter Min Typ Max Units
Serial Speed 2400   460800 bps
Power up delay: no card     200 ms
Power up delay: w/card 200 250 400+1 ms
Card initialization time2 30 80 200+1 ms
  1. Card communication timing will vary widely from brand to brand depending on many factors. 2

  2. This is the amount of time taken to initialize a card after insertion and a command has been sent, but before the command has been executed.