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Smart card interface, Stop mode (low-power mode) – Rainbow Electronics DS8314 User Manual

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DS8313/DS8314

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 DS8313/DS8314 enter low-power stop
mode.

Smart Card Interface

14

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CMDVCC

1_8V

5V/3V

STOP MODE

OFF

PRES

V

CC

DEACTIVATE INTERFACE

ACTIVATE

STOP MODE

DEACTIVATE

STOP MODE

220

μs DELAY

OFF FOLLOWS

PRES IN STOP MODE

OFF ASSERTED TO

WAIT FOR DELAY

8ms DEBOUNCE

Figure 8. Stop-Mode Sequence