ATmega16M1 Automotive Atmel Corporation, ATmega16M1 Automotive Datasheet - Page 272

• Manufacturer Part Number: ATmega16M1 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATmega16M1 Automotive

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 27
• Ext Interrupts: 27
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Uart: 1
• Can: 1
• Lin: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 125
• Analog Comparators: 4
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• 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 150
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 14
• Input Capture Channels: 1
• Pwm Channels: 10
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

21.3.1
21.4
21.4.1
272
DAC Register Description
Atmel ATmega16/32/64/M1/C1
DAC Voltage Reference
Digital to Analog Conversion Control Register – DACON
If the trigger signal is still set when the conversion completes, a new conversion will not be
started. If another positive edge occurs on the trigger signal during conversion, the edge will
be ignored.
Note that an interrupt flag will be set even if the specific interrupt is disabled or the Global
Interrupt Enable bit in SREG is cleared. A conversion can thus be triggered without causing an
interrupt. However, the interrupt flag must be cleared in order to trigger a new conversion at
the next interrupt event.
The reference voltage for the ADC (V
can be selected as either AV
AV
erated from the internal bandgap reference (V
the external AREF pin is directly connected to the DAC, and the reference voltage can be
made more immune to noise by connecting a capacitor between the AREF pin and ground.
V
a high impedant source, and only a capacitive load should be connected in a system.
If the user has a fixed voltage source connected to the AREF pin, the user may not use the
other reference voltage options in the application, as they will be shorted to the external volt-
age. If no external voltage is applied to the AREF pin, the user may switch between AV
2.56V as reference selection. The first DAC conversion result after switching reference voltage
source may be inaccurate, and the user is advised to discard this result.
The DAC is controlled via three dedicated registers:
Bit 7 – DAATE: DAC Auto Trigger Enable bit
Set this bit to update the DAC input value on the positive edge of the trigger signal selected
with the DACTS2-0 bit in DACON register.
Clear it to automatically update the DAC input when a value is written on DACH register.
Bit 6:4 – DATS2, DATS1, DATS0: DAC Trigger Selection bits
These bits are only necessary in case the DAC works in auto trigger mode. It means if DAATE
bit is set.
Bit
Read/Write
Initial Value
REF
• The DACON register which is used for DAC configuration
• DACH and DACL which are used to set the value to be converted.
CC
can also be measured at the AREF pin with a high impedant voltmeter. Note that V
is connected to the DAC through a passive switch. The internal 2.56V reference is gen-
DAATE
R/W
7
0
DATS2
R/W
6
0
CC
, internal 2.56V reference, or external AREF pin.
DATS1
R/W
5
0
REF
) indicates the conversion range for the DAC. V
DATS0
R/W
4
0
BG
) through an internal amplifier. In either case,
3
0
-
-
DALA
R/W
2
0
DAOE
R/W
1
0
DAEN
R/W
0
0
7647G–AVR–09/11
DACON
CC
REF
and
REF
is