ATmega649 Atmel Corporation, ATmega649 Datasheet - Page 232
![no-image](/images/manufacturer_photos/0/0/79/atmel_corporation_sml.jpg)
ATmega649
Manufacturer Part Number
ATmega649
Description
Manufacturer
Atmel Corporation
Specifications of ATmega649
Flash (kbytes)
64 Kbytes
Pin Count
64
Max. Operating Frequency
16 MHz
Cpu
8-bit AVR
# Of Touch Channels
16
Hardware Qtouch Acquisition
No
Max I/o Pins
54
Ext Interrupts
17
Usb Speed
No
Usb Interface
No
Spi
2
Twi (i2c)
1
Uart
1
Segment Lcd
100
Graphic Lcd
No
Video Decoder
No
Camera Interface
No
Adc Channels
8
Adc Resolution (bits)
10
Adc Speed (ksps)
15
Analog Comparators
1
Resistive Touch Screen
No
Temp. Sensor
No
Crypto Engine
No
Sram (kbytes)
4
Eeprom (bytes)
2048
Self Program Memory
YES
Dram Memory
No
Nand Interface
No
Picopower
No
Temp. Range (deg C)
-40 to 85
I/o Supply Class
1.8 to 5.5
Operating Voltage (vcc)
1.8 to 5.5
Fpu
No
Mpu / Mmu
no / no
Timers
3
Output Compare Channels
4
Input Capture Channels
1
Pwm Channels
4
32khz Rtc
Yes
Calibrated Rc Oscillator
Yes
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
ATmega649-16AU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Company:
Part Number:
ATmega649-16MU
Manufacturer:
Atmel
Quantity:
135
Part Number:
ATmega6490-16AI
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Company:
Part Number:
ATmega6490-16AU
Manufacturer:
Atmel
Quantity:
135
Company:
Part Number:
ATmega6490-16AUR
Manufacturer:
Atmel
Quantity:
1 500
Company:
Part Number:
ATmega6490A-AU
Manufacturer:
Atmel
Quantity:
1 250
Company:
Part Number:
ATmega6490A-AUR
Manufacturer:
Maxim
Quantity:
43
23.2.3
23.2.4
232
ATmega329/3290/649/6490
1/3 Duty and 1/3 Bias
1/4 Duty and 1/3 Bias
Figure 23-4. Driving a LCD with Two Common Terminals
1/3 bias is usually recommended for LCD with three common terminals (1/3 duty). Waveform is
shown in
COM1 is the voltage across a segment that is off.
Figure 23-5. Driving a LCD with Three Common Terminals
1/3 bias is optimal for LCD displays with four common terminals (1/4 duty). Waveform is shown
in
the voltage across a segment that is off.
Figure
-
-
2
1
2
1
2
1
1
2
-1
1
1
/
/
/
/
/
/
/
/
3
3
3
3
3
3
3
3
-V
/
/
/
V
V
V
V
V
V
V
V
V
V
V
2
2
2
GND
GND
GND
-V
V
V
V
V
V
V
GND
GND
GND
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
23-6. SEG0 - COM0 is the voltage across a segment that is on and SEG0 - COM1 is
Figure
LCD
LCD
LCD
LCD
LCD
LCD
LCD
Frame
Frame
23-5. SEG0 - COM0 is the voltage across a segment that is on and SEG0-
Frame
Frame
SEG0
COM0
SEG0 - COM0
SEG0
COM0
SEG0 - COM0
-
-
-1
2
1
2
1
2
1
1
2
1
1
/
/
/
/
/
/
/
/
3
3
3
3
3
3
3
3
/
/
/
-V
2
2
2
V
V
V
GND
V
V
V
GND
V
V
V
GND
V
V
-V
V
GND
V
V
GND
V
V
GND
V
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
Frame
Frame
Frame
Frame
SEG0
COM1
SEG0 - COM1
SEG0
COM1
SEG0 - COM1
2552K–AVR–04/11