ATTINY861A-SU Atmel, ATTINY861A-SU Datasheet - Page 35

• Manufacturer Part Number: ATTINY861A-SU
• Description: IC, MCU, 8BIT, 8K FLASH, 20SOIC
• Manufacturer: Atmel

Specifications of ATTINY861A-SU

• Controller Family/series: ATtiny
• No. Of I/o's: 16
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 20MHz
• No.: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 8KB
• Oscillator Type: External, Internal
• Rohs Compliant: Yes

7.1.2
7.1.3
7.1.4
7.2
8197B–AVR–01/10
Software BOD Disable
ADC Noise Reduction Mode
Power-Down Mode
Standby Mode
Idle mode enables the MCU to wake up from external triggered interrupts as well as internal
ones like the Timer Overflow. If wake-up from the Analog Comparator interrupt is not required,
the Analog Comparator can be powered down by setting the ACD bit in the Analog Comparator
Control and Status Register – ACSR. This will reduce power consumption in Idle mode. If the
ADC is enabled, a conversion starts automatically when this mode is entered.
When the SM1:0 bits are written to 01, the SLEEP instruction makes the MCU enter ADC Noise
Reduction mode, stopping the CPU but allowing the ADC, the external interrupts, and the
Watchdog to continue operating (if enabled). This sleep mode halts clk
while allowing the other clocks to run.
This mode improves the noise environment for the ADC, enabling higher resolution measure-
ments. If the ADC is enabled, a conversion starts automatically when this mode is entered. Apart
form the ADC Conversion Complete interrupt, only an External Reset, a Watchdog Reset, a
Brown-out Reset, an SPM/EEPROM ready interrupt, an external level interrupt on INT0 or a pin
change interrupt can wake up the MCU from ADC Noise Reduction mode.
When the SM1:0 bits are written to 10, the SLEEP instruction makes the MCU enter Power-
down mode. In this mode, the Oscillator is stopped, while the external interrupts, and the Watch-
dog continue operating (if enabled). Only an External Reset, a Watchdog Reset, a Brown-out
Reset, an external level interrupt on INT0, or a pin change interrupt can wake up the MCU. This
sleep mode halts all generated clocks, allowing operation of asynchronous modules, only.
When the SM1:0 bits are written to 11 and an external crystal/resonator clock option is selected,
the SLEEP instruction makes the MCU enter Standby mode. This mode is identical to Power-
down with the exception that the Oscillator is kept running. From Standby mode, the device
wakes up in six clock cycles.
When the Brown-out Detector (BOD) is enabled by BODLEVEL fuses (see
168), the BOD is actively monitoring the supply voltage during a sleep period. It is possible to
save power by disabling the BOD by software in Power-Down sleep mode. The sleep mode
power consumption will then be at the same level as when BOD is globally disabled by fuses.
If BOD is disabled by software, the BOD function is turned off immediately after entering the
sleep mode. Upon wake-up from sleep, BOD is automatically enabled again. This ensures safe
operation in case the V
When the BOD has been disabled, the wake-up time from sleep mode will be approximately
60µs to ensure that the BOD is working correctly before the MCU continues executing code.
BOD disable is controlled by the BODS (BOD Sleep) bit of BOD Control Register, see
– MCU Control Register” on page
Stand-By, while writing a zero keeps the BOD active. The default setting is zero, i.e. BOD active.
Writing to the BODS bit is controlled by a timed sequence and an enable bit, see
MCU Control Register” on page
CC
level has dropped during the sleep period.
37.
37. Writing this bit to one turns off BOD in Power-Down and
I/O
, clk
Table 18-4 on page
CPU
, and clk
“MCUCR –
“MCUCR
FLASH
35
,