ATMEGA32A-MNR Atmel, ATMEGA32A-MNR Datasheet - Page 25

• Manufacturer Part Number: ATMEGA32A-MNR
• Description: IC MCU AVR 32K 16MHZ 44VQFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32A-MNR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8. System Clock and Clock Options
8.1
8.1.1
8.1.2
8155C–AVR–02/11
Clock Systems and their Distribution
CPU Clock – clk
I/O Clock – clk
I/O
Figure 8-1
need not 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
ment and Sleep Modes” on page
Figure 8-1.
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/Counters, SPI, and USART.
The I/O clock is also used by the External Interrupt module, but note that some external inter-
rupts are detected by asynchronous logic, allowing such interrupts to be detected even if the I/O
clock is halted. Also note that address recognition in the TWI module is carried out asynchro-
nously when clk
CPU
Timer/Counter
Timer/Counter
Asynchronous
Oscillator
presents the principal clock systems in the AVR and their distribution. All of the clocks
Clock Distribution
I/O
is halted, enabling TWI address reception in all sleep modes.
General I/O
Modules
External RC
Oscillator
clk
clk
ASY
I/O
33. The clock systems are detailed
External Clock
ADC
Control Unit
AVR Clock
Multiplexer
clk
Clock
ADC
Source Clock
CPU Core
clk
Oscillator
clk
Crystal
CPU
Reset Logic
FLASH
Watchdog Clock
Crystal Oscillator
RAM
Low-frequency
Watchdog Timer
Figure
Watchdog
Oscillator
ATmega32A
8-1.
Flash and
EEPROM
““Power Manage-
Calibrated RC
Oscillator
25