ATmega168A Atmel Corporation, ATmega168A Datasheet - Page 99

no-image

ATmega168A

Manufacturer Part Number
ATmega168A
Description
Manufacturer
Atmel Corporation
Datasheets

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

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
ATmega168A-AU
Manufacturer:
ATMEL
Quantity:
464
Part Number:
ATmega168A-AU
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168A-AU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Part Number:
ATmega168A-AUR
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168A-CCU
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168A-CCUR
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168A-MU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Part Number:
ATmega168A-PU
Manufacturer:
ATMEL
Quantity:
1 000
15.5
8271D–AVR–05/11
Output Compare Unit
The counting sequence is determined by the setting of the WGM01 and WGM00 bits located in
the Timer/Counter Control Register (TCCR0A) and the WGM02 bit located in the Timer/Counter
Control Register B (TCCR0B). There are close connections between how the counter behaves
(counts) and how waveforms are generated on the Output Compare outputs OC0A and OC0B.
For more details about advanced counting sequences and waveform generation, see
Operation” on page
The Timer/Counter Overflow Flag (TOV0) is set according to the mode of operation selected by
the WGM02:0 bits. TOV0 can be used for generating a CPU interrupt.
The 8-bit comparator continuously compares TCNT0 with the Output Compare Registers
(OCR0A and OCR0B). Whenever TCNT0 equals OCR0A or OCR0B, the comparator signals a
match. A match will set the Output Compare Flag (OCF0A or OCF0B) at the next timer clock
cycle. If the corresponding interrupt is enabled, the Output Compare Flag generates an Output
Compare interrupt. The Output Compare Flag is automatically cleared when the interrupt is exe-
cuted. Alternatively, the flag can be cleared by software by writing a logical one to its I/O bit
location. The Waveform Generator uses the match signal to generate an output according to
operating mode set by the WGM02:0 bits and Compare Output mode (COM0x1:0) bits. The max
and bottom signals are used by the Waveform Generator for handling the special cases of the
extreme values in some modes of operation
Figure 15-3
Figure 15-3. Output Compare Unit, Block Diagram
The OCR0x Registers are double buffered when using any of the Pulse Width Modulation
(PWM) modes. For the normal and Clear Timer on Compare (CTC) modes of operation, the dou-
ble buffering is disabled. The double buffering synchronizes the update of the OCR0x Compare
Registers to either top or bottom of the counting sequence. The synchronization prevents the
occurrence of odd-length, non-symmetrical PWM pulses, thereby making the output glitch-free.
shows a block diagram of the Output Compare unit.
bottom
FOCn
top
101.
ATmega48A/PA/88A/PA/168A/PA/328/P
OCRnx
Waveform Generator
WGMn1:0
=
(8-bit Comparator )
DATA BUS
(”Modes of Operation” on page
COMnx1:0
TCNTn
OCFnx (Int.Req.)
OCnx
101).
”Modes of
99

Related parts for ATmega168A