The manual states the maximum consumption based on SD/MMC card standards.

Here is our measurements for a Lexar 64MB MMC card. Current measurements may vary with different cards.

uMMC Power Consumption

@5.0V  nominal  maximum
idle   8.5 mA   15.0 mA
read   15.0 mA  30.0 mA
write  40.0 mA  60.0 mA