ATMEGA644A-AU Atmel, ATMEGA644A-AU Datasheet - Page 251
ATMEGA644A-AU
Manufacturer Part Number
ATMEGA644A-AU
Description
IC MCU AVR 64K FLASH 44TQFP
Manufacturer
Atmel
Series
AVR® ATmegar
Specifications of ATMEGA644A-AU
Core Processor
AVR
Core Size
8-Bit
Speed
20MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
32
Program Memory Size
64KB (32K x 16)
Program Memory Type
FLASH
Eeprom Size
2K x 8
Ram Size
4K x 8
Voltage - Supply (vcc/vdd)
1.8 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
44-TQFP, 44-VQFP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
ATMEGA644A-AU
Manufacturer:
Atmel
Quantity:
135
- Current page: 251 of 581
- Download datasheet (27Mb)
22.7.2
22.7.3
8272A–AVR–01/10
Analog Noise Canceling Techniques
Offset Compensation Schemes
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 22-9. ADC Power Connections
The gain stage has a built-in offset cancellation circuitry that nulls the offset of differential mea-
surements as much as possible. The remaining offset in the analog path can be measured
directly by selecting the same channel for both differential inputs. This offset residue can be then
subtracted in software from the measurement results. Using this kind of software based offset
correction, offset on any channel can be reduced below one LSB.
164A/164PA/324A/324PA/644A/644PA/1284/1284P
a. Keep analog signal paths as short as possible. Make sure analog tracks run over the
b. The AVCC pin on the device should be connected to the digital V
c. Use the ADC noise canceler function to reduce induced noise from the CPU.
d. If any ADC port pins are used as digital outputs, it is essential that these do not
analog ground plane, and keep them well away from high-speed switching digital
tracks.
via an LC network as shown in
switch while a conversion is in progress.
Figure
22-9.
PA4 (ADC4)
PA5 (ADC5)
PA6 (ADC6)
PA7 (ADC7)
AREF
GND
AVCC
PC7
CC
supply voltage
251
Related parts for ATMEGA644A-AU
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ COM 64-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ IND 64-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ COM 64-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 64KB FLASH 16MHZ 64TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 64KB FLASH 16MHZ 64QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ IND 64-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC MCU AVR 64K 5V 16MHZ 64-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC MCU AVR 64K 5V 16MHZ 64-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU 8-Bit ATmega AVR RISC 64KB Flash 5V 64-Pin TQFP T/R
Manufacturer:
Atmel
Datasheet: