Table 1.
Port Signal Description (Continued)
Internal
Port
CV
CC
Signal
Name
Power
Supply
ESD
Type
PWR
Description
Card Supply Voltage
CV
CC
is the programmable voltage output for the Card interface. It must be connected
to an external decoupling capacitor.
DV
CC
PWR
Digital Supply Voltage
DV
CC
is used to supply the digital core and internal I/Os. It is internally connected to the
output of a 3V regulator and must be connected to an external decoupling capacitor.
EV
CC
V
CC
PWR
Extra Supply Voltage
EV
CC
is used to supply the level shifters of UART interface I/O pins. It must be
connected to an external decoupling capacitor. This reference voltage is generated
internally (automatically or not), or it can be connected to an external voltage
reference.
CVSS
GND
DC/DC Ground
CVSS is used to sink high shunt currents from the external coil.
VSS
GND
Ground
6
AT83C21GC
4247DS–SCR–03/07
ATMEL [ ATMEL CORPORATION ]
