DS8005 Maxim, DS8005 Datasheet - Page 15

• Manufacturer Part Number: DS8005
• Description: The DS8005 dual smart card interface is a low-cost, dual analog front-end for an IC card reader interface that needs to communicate with two smart cards in a mutually exclusive fashion
• Manufacturer: Maxim

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
Figure 8. Stop-Mode Sequence
STOP MODE
Stop Mode (Low-Power Mode)
CMDVCC
PRES_
5V/3V
1_8V
OFF_
V
CC_
DEACTIVATE INTERFACE
______________________________________________________________________________________
PRES IN STOP MODE
OFF_ FOLLOWS
STOP MODE
ACTIVATE
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
stabilize. This prevents smart card access from occur-
ring after leaving 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 device enters low-power stop mode.
220μs DELAY
DEACTIVATE
STOP MODE
Smart Card Interface
OFF_ ASSERTED TO
WAIT FOR DELAY
8ms DEBOUNCE
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