Datasheet

73S8009C Data Sheet DS_8009C_025

22 Rev. 1.5

CMDVCC

RST

CLK

I/O

VCC_ON

VCC

t1 t2 t3

Figure 6: 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 7 shows the timing diagram for the signals CMDVCC (#/%), PRES, and OFF during a card session

and outside the card session.

PRES

OFF

CMDVCC

VCC

outside card session within card session

OFF is low by

card extracted

OFF is low by

any fault

within card

session

Figure 7: OFF Activity