ATmega168A

Manufacturer Part NumberATmega168A
ManufacturerAtmel Corporation
ATmega168A datasheets
 

Specifications of ATmega168A

Flash (kbytes)16 KbytesPin Count32
Max. Operating Frequency20 MHzCpu8-bit AVR
# Of Touch Channels16Hardware Qtouch AcquisitionNo
Max I/o Pins23Ext Interrupts24
Usb SpeedNoUsb InterfaceNo
Spi2Twi (i2c)1
Uart1Graphic LcdNo
Video DecoderNoCamera InterfaceNo
Adc Channels8Adc Resolution (bits)10
Adc Speed (ksps)15Analog Comparators1
Resistive Touch ScreenNoTemp. SensorYes
Crypto EngineNoSram (kbytes)1
Eeprom (bytes)512Self Program MemoryYES
Dram MemoryNoNand InterfaceNo
PicopowerNoTemp. Range (deg C)-40 to 85
I/o Supply Class1.8 to 5.5Operating Voltage (vcc)1.8 to 5.5
FpuNoMpu / Mmuno / no
Timers3Output Compare Channels6
Input Capture Channels1Pwm Channels6
32khz RtcYesCalibrated Rc OscillatorYes
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certain time for the voltage to stabilize. If not stabilized, the first conversion may give a wrong
value. See
• Bit 5 – ACO: Analog Comparator Output
The output of the Analog Comparator is synchronized and then directly connected to ACO. The
synchronization introduces a delay of 1 - 2 clock cycles.
• Bit 4 – ACI: Analog Comparator Interrupt Flag
This bit is set by hardware when a comparator output event triggers the interrupt mode defined
by ACIS1 and ACIS0. The Analog Comparator interrupt routine is executed if the ACIE bit is set
and the I-bit in SREG is set. ACI is cleared by hardware when executing the corresponding inter-
rupt handling vector. Alternatively, ACI is cleared by writing a logic one to the flag.
• Bit 3 – ACIE: Analog Comparator Interrupt Enable
When the ACIE bit is written logic one and the I-bit in the Status Register is set, the Analog Com-
parator interrupt is activated. When written logic zero, the interrupt is disabled.
• Bit 2 – ACIC: Analog Comparator Input Capture Enable
When written logic one, this bit enables the input capture function in Timer/Counter1 to be trig-
gered by the Analog Comparator. The comparator output is in this case directly connected to the
input capture front-end logic, making the comparator utilize the noise canceler and edge select
features of the Timer/Counter1 Input Capture interrupt. When written logic zero, no connection
between the Analog Comparator and the input capture function exists. To make the comparator
trigger the Timer/Counter1 Input Capture interrupt, the ICIE1 bit in the Timer Interrupt Mask
Register (TIMSK1) must be set.
• Bits 1, 0 – ACIS1, ACIS0: Analog Comparator Interrupt Mode Select
These bits determine which comparator events that trigger the Analog Comparator interrupt. The
different settings are shown in
Table 23-2.
ACIS1
0
0
1
1
When changing the ACIS1/ACIS0 bits, the Analog Comparator Interrupt must be disabled by
clearing its Interrupt Enable bit in the ACSR Register. Otherwise an interrupt can occur when the
bits are changed.
8271D–AVR–05/11
ATmega48A/PA/88A/PA/168A/PA/328/P
”Internal Voltage Reference” on page 51
Table
23-2.
ACIS1/ACIS0 Settings
ACIS0
Interrupt Mode
0
Comparator Interrupt on Output Toggle.
1
Reserved
0
Comparator Interrupt on Falling Output Edge.
1
Comparator Interrupt on Rising Output Edge.
250