ATtiny461A Atmel Corporation, ATtiny461A Datasheet - Page 159

• Manufacturer Part Number: ATtiny461A
• Manufacturer: Atmel Corporation

Specifications of ATtiny461A

• Flash (kbytes): 4 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 20 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): 0.25
• Eeprom (bytes): 256
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• 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: 2
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

15.13.4
8197C–AVR–05/11
ADCSRB – ADC Control and Status Register B
If these bits are changed during a conversion, the change will not go into effect until this conver-
sion is complete (ADIF in ADCSRA is set).
• 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.
• Bit 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.
• Bit 5 – Res: Reserved Bit
This bit is reserved and will always read zero.
• Bit 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
15-4. If active channels are used, using AVCC or an external AREF higher than (AVCC - 1V) is
not recommended, as this will affect ADC accuracy.
• Bit 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 – ADTS[2:0]: 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 ADTS[2:0] settings will have no effect. A conver-
sion will be triggered by the rising edge of the selected Interrupt Flag. Note that switching from a
trigger source that is cleared to a trigger source that is set, will generate a positive edge on the
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
ATtiny261A/461A/861A
MUX5
R/W
3
0
ADTS2
R/W
2
0
ADTS1
R/W
1
0
ADTS0
R/W
0
0
Table 15-5
ADCSRB
Table
159
for