AT90USB82/162
7. Power Distribution
The AT90USB82/162 product includes an internal 5V to 3.3V regulator that
allows to supply the USB pad (see Figure 7-1.) and, depending on the applica-
tion, external components or even the microcontroller itself (see Figure 7-2.).
Figure 7-1. 5V configuration
USB or PS/2 connector
VBus or PS/2 Vcc (5V)
UVCC
UCAP
VCC
AVCC
PS/2 Pad
Band
Gap
I/O POR
BOD
PLL Comparator
AVR Core
3.3V Reg
USB Pad
UVSS
VSS
Figure 7-2. 5V / 3.3V configuration
USB or PS/2 connector
at least 50 mA
for external chips
VBus or PS/2 Vcc (5V)
(3.3V)
UVCC
UCAP
VCC
AVCC
PS/2 Pad
Band
Gap
I/O POR
BOD
PLL Comparator
AVR Core
3.3V Reg
USB Pad
UVSS
VSS
39
7707D–AVR–07/08
ATMEL [ ATMEL ]
