AT89C5131A-L_14 Datasheet, PDF (10/186 Pages) ATMEL Corporation – Maximum Core Frequency 48 MHz in X1 Mode, 24 MHz in X2 Mode

Table 12. Power Signal Description
Signal
Name Type Description
AVSS
GND
Alternate Ground
AVSS is used to supply the on-chip PLL and the USB PAD.
AVDD
PWR
Alternate Supply Voltage
AVDD is used to supply the on-chip PLL and the USB PAD.
VSS
GND
Digital Ground
VSS is used to supply the buffer ring and the digital core.
VDD
PWR
Digital Supply Voltage
VDD is used to supply the buffer ring on all versions of the device.
It is also used to power the on-chip voltage regulator of the Standard
versions or the digital core of the Low Power versions.
VREF
USB pull-up Controlled Output
O ^{VREF is used to control the USB D+ 1.5 kΩ pull up.}
The Vref output is in high impedance when the bit DETACH is set in the
USBCON register.
Alternate
Function
-
-
-
-
-
10 AT89C5131A-L
4338F–USB–08/07