DS8113 Datasheet, PDF (14/17 Pages) Maxim Integrated Products – Smart Card Interface

Smart Card Interface
Stop Mode (Low-Power Mode)
A low-power state, stop mode, can be entered by forc-
ing the CMDVCC, 5V/3V, and 1_8V input pins to a
logic-high state. Stop mode can only be entered when
the smart card interface is inactive. In stop mode all
internal analog circuits are disabled. The OFF pin fol-
lows the status of the PRES pin. To exit stop mode,
change the state of one or more of the three control
pins to a logic-low. An internal 220µs (typ) power-up
delay and the 8ms PRES debounce delay are in effect
and OFF is asserted to allow the internal circuitry to sta-
bilize. This prevents smart card access from occurring
after leaving the stop mode. Figure 8 shows the control
sequence for entering and exiting stop mode. Note that
an in-progress deactivation sequence always finishes
before the DS8113 enters low-power stop mode.
DEACTIVATE INTERFACE
CMDVCC
1_8V
5V/3V
ACTIVATE
STOP MODE
STOP MODE
OFF
OFF FOLLOWS
PRES IN STOP MODE
PRES
DEACTIVATE
STOP MODE
220µs DELAY
8ms DEBOUNCE
OFF ASSERTED TO
WAIT FOR DELAY
VCC
Figure 8. Stop-Mode Sequence
14 ______________________________________________________________________________________