AT89C5122 ATMEL [ATMEL Corporation], AT89C5122 Datasheet - Page 93

• Manufacturer Part Number: AT89C5122
• Description: MICROCONTROLLER WITH USB AND SMART CARD READER INTERFACES
• Manufacturer: ATMEL [ATMEL Corporation]

Monitoring Procedure
Table 60. DC/DC converter status
4202D–SCR–06/05
VCARDOK
0
0
1
1
ICARDOVF
0
1
0
1
Incrementation of BOOST[1:0] bits increases at the same time the current overflow level
in the same proportion as the startup current. So once the DC/DC converter is ready it is
advised to decrement the BOOST[1:0] bits to restore the overflow current to its normal
or desired value.
Once the DC/DC has been successfuly initialized, it is necessary to monitor the DC/DC
converter by means of bits VCARDOK and ICARDOVF in the SCISR register.
DC/DC Status
- Not Started or switched off by application.
The current overflow sensor is disabled during the DC/DC converter startup. Then if a current
overflow condition is applied during the DC/DC converter startup, the DC/DC converter is unable
to start and both bits VCARDOK and ICARDOVF remains at 0.
DC/DC converter correctly started then the output voltage is out of ISO/IEC 7816-3
specifications. In this case the firmware must take appropriate actions like deactivating the
DC/DC converter in compliance with ISO/IEC 7816.
Started and automatically switched off by a current overflow condition
Operating properly according to ISO/IEC 7816-3 and EMV recommendations
Not applicable
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