ATtiny20 Atmel Corporation, ATtiny20 Datasheet - Page 27

• Manufacturer Part Number: ATtiny20
• Manufacturer: Atmel Corporation

Specifications of ATtiny20

• Flash (kbytes): 2 Kbytes
• Pin Count: 14
• Max. Operating Frequency: 12 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 5
• Hardware Qtouch Acquisition: Yes
• Max I/o Pins: 12
• Ext Interrupts: 12
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 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): 0.12
• Self Program Memory: NO
• 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: 2
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 3
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

7.3
7.4
7.4.1
7.4.2
7.4.3
7.4.4
8235B–AVR–04/11
Power Reduction Register
Minimizing Power Consumption
Analog Comparator
Analog to Digital Converter
Watchdog Timer
Brown-out Detector
The Power Reduction Register (PRR), see
vides a method to reduce power consumption by stopping the clock to individual peripherals.
When the clock for a peripheral is stopped then:
The peripheral should in most cases be disabled before stopping the clock. Clearing the PRR bit
wakes up the peripheral and puts it in the same state as before shutdown.
Peripheral shutdown can be used in Idle mode and Active mode to significantly reduce the over-
all power consumption. See
other sleep modes, the clock is already stopped.
There are several issues to consider when trying to minimize the power consumption in an AVR
Core controlled system. In general, sleep modes should be used as much as possible, and the
sleep mode should be selected so that as few as possible of the device’s functions are operat-
ing. All functions not needed should be disabled. In particular, the following modules may need
special consideration when trying to achieve the lowest possible power consumption.
When entering Idle mode, the analog comparator should be disabled if not used. In the power-
down mode, the analog comparator is automatically disabled. See
page 108
If enabled, the ADC will be enabled in all sleep modes. To save power, the ADC should be dis-
abled before entering any sleep mode. When the ADC is turned off and on again, the next
conversion will be an extended conversion. See
details on ADC operation.
If the Watchdog Timer is not needed in the application, this module should be turned off. If the
Watchdog Timer is enabled, it will be enabled in all sleep modes, and hence, always consume
power. In the deeper sleep modes, this will contribute significantly to the total current consump-
tion. Refer to
If the Brown-out Detector is not needed in the application, this module should be turned off. If the
Brown-out Detector is enabled by the BODLEVEL Fuses, it will be enabled in all sleep modes,
and hence, always consume power. In the deeper sleep modes, this will contribute significantly
to the total current consumption. See
able” on page 26
• The current state of the peripheral is frozen.
• The associated registers can not be read or written.
• Resources used by the peripheral will remain occupied.
for further details.
“Watchdog Timer” on page 33
for details on how to configure the Brown-out Detector.
“Supply Current of I/O Modules” on page 179
“Brown-out Detection” on page 32
“PRR – Power Reduction Register” on page
for details on how to configure the Watchdog Timer.
“Analog to Digital Converter” on page 112
“Analog Comparator” on
and
“Software BOD Dis-
for examples. In all
ATtiny20
29, pro-
for
27