Rainbow Electronics AT89C5122 - Manual (Page 93)

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AT8xC5122/23
4202E–SCR–06/06
advised to decrement the BOOST[1:0] bits to restore the overflow current to its normal
or desired value.
Monitoring Procedure 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.
Table 60. DC/DC converter status
VCARDOK ICARDOVF DC/DC Status
0 0
- 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.
0 1 Started and automatically switched off by a current overflow condition
1 0 Operating properly according to ISO/IEC 7816-3 and EMV recommendations
1 1 Not applicable