ATtiny861 Automotive Atmel Corporation, ATtiny861 Automotive Datasheet - Page 162

• Manufacturer Part Number: ATtiny861 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATtiny861 Automotive

• Flash (kbytes): 8 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 8
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 16
• Ext Interrupts: 16
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.5
• 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: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

19.10.4
162
ATtiny261/ATtiny461/ATtiny861
ADCSRB – ADC Control and Status Register B
• Bit 7– BIN: Bipolar Input Mode
The gain stage is working in the unipolar mode as default, but the bipolar mode can be selected
by writing the BIN bit in the ADCSRB register. In the unipolar mode only one-sided conversions
are supported and the voltage on the positive input must always be larger than the voltage on
the negative input. Otherwise the result is saturated to the voltage reference. In the bipolar mode
two-sided conversions are supported and the result is represented in the two’s complement
form. In the unipolar mode the resolution is 10 bits and the bipolar mode the resolution is 9 bits +
1 sign bit.
• Bits 6 – GSEL: Gain Select
The Gain Select bit selects the 32x gain instead of the 20x gain and the 8x gain instead of the 1x
gain when the Gain Select bit is written to one.
• Bits 5 – Res: Reserved Bit
This bit is a reserved bit in the ATtiny261/461/861 and will always read as zero.
• Bits 4 – REFS2: Reference Selection Bit
These bit selects either the voltage reference of 1.1 V or 2.56 V for the ADC, as shown in
19-4. If active channels are used, using AVCC or an external AREF higher than (AVCC - 1V) is
not recommended, as this will affect ADC accuracy. The internal voltage reference options may
not be used if an external voltage is being applied to the AREF pin.
• Bits 3 – MUX5: Analog Channel and Gain Selection Bit 5
The MUX5 bit is the MSB of the Analog Channel and Gain Selection bits. Refer to
details. If this bit is changed during a conversion, the change will not go into effect until this
conversion is complete (ADIF in ADCSRA is set).
• Bits 2:0 – ADTS2:0: ADC Auto Trigger Source
If ADATE in ADCSRA is written to one, the value of these bits selects which source will trigger
an ADC conversion. If ADATE is cleared, the ADTS2:0 settings will have no effect. A conversion
will be triggered by the rising edge of the selected Interrupt Flag. Note that switching from a trig-
ger source that is cleared to a trigger source that is set, will generate a positive edge on the
trigger signal. If ADEN in ADCSRA is set, this will start a conversion. Switching to Free Running
mode (ADTS[2:0]=0) will not cause a trigger event, even if the ADC Interrupt Flag is set.
Bit
0x03 (0x23)
Read/Write
Initial Value
R/W
BIN
7
0
GSEL
R/W
6
0
R
5
0
-
REFS2
R/W
4
0
MUX5
R/W
3
0
ADTS2
R/W
2
0
ADTS1
R/W
1
0
ADTS0
R/W
0
0
Table 19-5
7753F–AVR–01/11
ADCSRB
Table
for