ATmega168A Atmel Corporation, ATmega168A Datasheet - Page 162

• Manufacturer Part Number: ATmega168A
• Manufacturer: Atmel Corporation

Specifications of ATmega168A

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 24
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• 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: Yes
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• 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: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

8271D–AVR–05/11
Note:
Table 18-7
rect PWM mode.
Table 18-7.
Note:
• Bits 3, 2 – Reserved
These bits are reserved bits in the ATmega48A/PA/88A/PA/168A/PA/328/P and will always read
as zero.
• Bits 1:0 – WGM21:0: Waveform Generation Mode
Combined with the WGM22 bit found in the TCCR2B Register, these bits control the counting
sequence of the counter, the source for maximum (TOP) counter value, and what type of wave-
form generation to be used, see
unit are: Normal mode (counter), Clear Timer on Compare Match (CTC) mode, and two types of
Pulse Width Modulation (PWM) modes (see
Table 18-8.
Notes:
Mode
COM2B1
0
1
2
3
4
5
6
7
0
0
1
1
1. A special case occurs when OCR2B equals TOP and COM2B1 is set. In this case, the Com-
1. A special case occurs when OCR2B equals TOP and COM2B1 is set. In this case, the Com-
1. MAX= 0xFF
2. BOTTOM= 0x00
WGM2
pare Match is ignored, but the set or clear is done at BOTTOM. See
Mode” on page 154
pare Match is ignored, but the set or clear is done at TOP. See
page 154
shows the COM2B1:0 bit functionality when the WGM22:0 bits are set to phase cor-
0
0
0
0
1
1
1
1
Compare Output Mode, Phase Correct PWM Mode
Waveform Generation Mode Bit Description
COM2B0
for more details.
WGM1
ATmega48A/PA/88A/PA/168A/PA/328/P
0
1
0
1
0
0
1
1
0
0
1
1
for more details.
Description
Normal port operation, OC2B disconnected.
Reserved
Clear OC2B on Compare Match when up-counting. Set OC2B on
Compare Match when down-counting.
Set OC2B on Compare Match when up-counting. Clear OC2B on
Compare Match when down-counting.
WGM0
Table
0
1
0
1
0
1
0
1
18-8. Modes of operation supported by the Timer/Counter
Timer/Counter
Mode of
Operation
Normal
PWM, Phase
Correct
CTC
Fast PWM
Reserved
PWM, Phase
Correct
Reserved
Fast PWM
”Modes of Operation” on page
OCRA
OCRA
OCRA
0xFF
0xFF
0xFF
TOP
–
–
(1)
”Phase Correct PWM Mode” on
Immediate
Immediate
Update of
BOTTOM
BOTTOM
OCRx at
TOP
TOP
”Phase Correct PWM
–
–
151).
Set on
TOV Flag
BOTTOM
BOTTOM
MAX
MAX
MAX
TOP
–
–
(1)(2)
162