
5
6384DS–ATARM–13-Jan-10
AT91SAM9G20 Summary
3.
Signal Description
Table 3-1.
Signal Description List (Continued)
Signal Name
Function
Type
Active
Level
Comments
Power Supplies
VDDIOM
EBI I/O Lines Power Supply
Power
1.65V to 1.95V or 3.0V to 3.6V
VDDIOP
Peripherals I/O Lines Power Supply
Power
1.65V to 3.6V
VDDBU
Backup I/O Lines Power Supply
Power
0.9V to 1.1V
VDDANA
Analog Power Supply
Power
3.0V to 3.6V
VDDPLL
PLL Power Supply
Power
0.9V to 1.1V
VDDOSC
Oscillator Power Supply
Power
1.65V to 3.6V
VDDCORE
Core Chip Power Supply
Power
0.9V to 1.1V
VDDUSB
USB Power Supply
Power
1.65V to 3.6V
GND
Ground
GNDANA
Analog Ground
Ground
GNDBU
Backup Ground
Ground
GNDUSB
USB Ground
Ground
GNDPLL
PLL Ground
Ground
Clocks, Oscillators and PLLs
XIN
Main Oscillator Input
Input
XOUT
Main Oscillator Output
Output
XIN32
Slow Clock Oscillator Input
Input
XOUT32
Slow Clock Oscillator Output
Output
OSCSEL
Slow Clock Oscillator Selection
Input
Accepts between 0V and
VDDBU.
PCK0 - PCK1
Programmable Clock Output
Output
Shutdown, Wakeup Logic
SHDN
Shutdown Control
Output
WKUP
Wake-up Input
Input
Accepts between 0V and
VDDBU.
ICE and JTAG
NTRST
Test Reset Signal
Input
Low
Pull-up resistor
TCK
Test Clock
Input
No pull-up resistor
TDI
Test Data In
Input
No pull-up resistor
TDO
Test Data Out
Output
TMS
Test Mode Select
Input
No pull-up resistor
JTAGSEL
JTAG Selection
Input
Pull-down resistor. Accepts
between 0V and VDDBU.
RTCK
Return Test Clock
Output