XTAL2
AVCC
AREF
LCDCAP
Resources
Output from the inverting Oscillator amplifier.
AVCC is the supply voltage pin for Port F and the A/D Converter. It should be externally
connected to VCC, even if the ADC is not used. If the ADC is used, it should be con-
nected to VCC through a low-pass filter.
This is the analog reference pin for the A/D Converter.
An external capacitor (typical > 470 nF) must be connected to the LCDCAP pin as
shown in Figure 99. This capacitor acts as a reservoir for LCD power (VLCD). A large
capacitance reduces ripple on VLCD but increases the time until VLCD reaches its target
value.
A comprehensive set of development tools, application notes and datasheets are avail-
able for download on http://www.atmel.com/avr.
8 ATmega329/3290/649/6490
2552HS–AVR–11/06