73S8009C Data Sheet
DS_8009C_025
CMDVCC
RST
CLK
I/O
VCC_ON
VCC
t1
t2
t3
t4
t5
Figure 7: Deactivation Sequence
3.7 OFF and Fault Detection
There are two different cases that the system controller can monitor the OFF signal: to query regarding
the card presence outside card sessions, or for fault detection during card sessions.
Outside a card session: In this condition, CMDVCC (#/%) are always high, OFF is low if the card is not
present, and high if the card is present. Because it is outside a card session, no fault detection can occur
and it will not act upon the OFF signal. No deactivation is required during this time.
During a card session: CMDVCC# and/or CMDVCC% is always low, and OFF falls low if the card is
extracted or if any fault detection is detected. At the same time that OFF is set low, the sequencer starts
the deactivation process and the host should stop all transitions on the signal lines.
Figure 8 shows the timing diagram for the signals CMDVCC (#/%), PRES, and OFF during a card session
and outside the card session.
OFF is low by
OFF is low by
card extracted
any fault
PRES
OFF
CMDVCC
VCC
outside card session
within card session
within card
session
Figure 8: OFF Activity
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Rev. 1.4
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
