ATmega640 Atmel Corporation, ATmega640 Datasheet - Page 272

• Manufacturer Part Number: ATmega640
• Manufacturer: Atmel Corporation

Specifications of ATmega640

• Flash (kbytes): 64 Kbytes
• Pin Count: 100
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 86
• Ext Interrupts: 32
• Usb Speed: No
• Usb Interface: No
• Spi: 5
• Twi (i2c): 1
• Uart: 4
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 16
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 8
• Eeprom (bytes): 4096
• 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: 6
• Output Compare Channels: 16
• Input Capture Channels: 4
• Pwm Channels: 15
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

25.2
25.2.1
25.2.2
2549N–AVR–05/11
Register Description
ADCSRB – ADC Control and Status Register B
ACSR – Analog Comparator Control and Status Register
Table 25-1.
• Bit 6 – ACME: Analog Comparator Multiplexer Enable
When this bit is written logic one and the ADC is switched off (ADEN in ADCSRA is zero), the
ADC multiplexer selects the negative input to the Analog Comparator. When this bit is written
logic zero, AIN1 is applied to the negative input of the Analog Comparator. For a detailed
description of this bit, see
• Bit 7 – ACD: Analog Comparator Disable
When this bit is written logic one, the power to the Analog Comparator is switched off. This bit
can be set at any time to turn off the Analog Comparator. This will reduce power consumption in
Active and Idle mode. When changing the ACD bit, the Analog Comparator Interrupt must be
disabled by clearing the ACIE bit in ACSR. Otherwise an interrupt can occur when the bit is
changed.
Bit
(0x7B)
Read/Write
Initial Value
Bit
0x30 (0x50)
Read/Write
Initial Value
ACME
1
1
1
1
1
1
1
1
1
1
1
1
Analog Comparator Mulitiplexed Input (Continued)
ADEN
ACD
R/W
R
7
0
7
–
0
0
0
0
0
0
0
0
0
0
0
0
0
ACBG
ACME
R/W
R/W
6
0
6
0
“Analog Comparator Multiplexed Input” on page
MUX5
0
0
0
0
1
1
1
1
1
1
1
1
ACO
N/A
R
ATmega640/1280/1281/2560/2561
5
R
5
–
0
MUX2:0
R/W
ACI
100
101
110
111
000
001
010
011
100
101
110
111
4
0
R
4
–
0
ACIE
MUX5
R/W
R/W
3
0
3
0
ADC4
ADC5
ADC6
ADC7
ADC8
ADC9
ADC10
ADC11
ADC12
ADC13
ADC14
ADC15
ADTS2
ACIC
Analog Comparator Negative Input
R/W
R/W
2
0
2
0
ACIS1
ADTS1
R/W
R/W
1
0
1
0
ACIS0
ADTS0
R/W
R/W
0
0
0
0
271.
ADCSRB
ACSR
272