ATTINY861A-XU Atmel, ATTINY861A-XU Datasheet - Page 24

• Manufacturer Part Number: ATTINY861A-XU
• Description: Microcontrollers (MCU) 8K Flash;125B EEPROM 128B SRAM;16 IO Pins
• Manufacturer: Atmel

Specifications of ATTINY861A-XU

• Core: RISC
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 8 KB
• Data Ram Size: 512 B
• Interface Type: SPI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 16
• Operating Supply Voltage: 1.8 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: TSSOP-20
• Minimum Operating Temperature: - 40 C
• Lead Free Status / Rohs Status: Details

6. Clock System
6.1
6.1.1
6.1.2
24
Clock Subsystems
ATtiny261A/461A/861A
CPU Clock – clk
I/O Clock – clk
I/O
Figure 6-1
be active at a given time. In order to reduce power consumption, the clocks to modules not being
used can be halted by using different sleep modes, as described in
Sleep Modes” on page
Figure 6-1.
The clock subsystems are detailed in the sections below.
The CPU clock is routed to parts of the system concerned with operation of the AVR core.
Examples of such modules are the General Purpose Register File, the Status Register and the
Data memory holding the Stack Pointer. Halting the CPU clock inhibits the core from performing
general operations and calculations.
The I/O clock is used by the majority of the I/O modules, like Timer/Counter. The I/O clock is
also used by the External Interrupt module, but note that some external interrupts are detected
by asynchronous logic, allowing such interrupts to be detected even if the I/O clock is halted.
CPU
clk
PCK
General I/O
Modules
Oscillator
PLL
presents the principal clock systems and their distribution. All of the clocks need not
clk
PLL
Clock Distribution
General I/O
Modules
External Clock
clk
34.
I/O
Source clock
System Clock
Control Unit
AVR Clock
Multiplexer
Prescaler
Clock
ADC
Oscillator
Crystal
clk
ADC
clk
clk
Crystal Oscillator
CPU
Low-Frequency
FLASH
Calibrated RC
Oscillator
CPU Core
Reset Logic
Watchdog clock
Watchdog Timer
RAM
“Power Management and
Watchdog
Oscillator
Flash and
8197B–AVR–01/10
EEPROM
Calibrated RC
Oscillator