ATMEGA169 ATMEL [ATMEL Corporation], ATMEGA169 Datasheet - Page 201

• Manufacturer Part Number: ATMEGA169
• Description: 8-bit Microcontroller with 16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Analog Noise Canceling
Techniques
2514P–AVR–07/06
Digital circuitry inside and outside the device generates EMI which might affect the
accuracy of analog measurements. If conversion accuracy is critical, the noise level can
be reduced by applying the following techniques:
Figure 91. ADC Power Connections
1. Keep analog signal paths as short as possible. Make sure analog tracks run
2. The AVCC pin on the device should be connected to the digital V
3. Use the ADC noise canceler function to reduce induced noise from the CPU.
4. If any ADC port pins are used as digital outputs, it is essential that these do
over the analog ground plane, and keep them well away from high-speed
switching digital tracks.
voltage via an LC network as shown in Figure 91.
not switch while a conversion is in progress.
Analog Ground Plane
100nF
(ADC7) PF7
(ADC6) PF6
(ADC5) PF5
(ADC4) PF4
(ADC3) PF3
(ADC2) PF2
(ADC1) PF1
(ADC0) PF0
AREF
AVCC
GND
GND
VCC
PA0
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ATmega169/V
CC
supply
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