ATMEGA64-16AI Atmel, ATMEGA64-16AI Datasheet - Page 38

• Manufacturer Part Number: ATMEGA64-16AI
• Description: IC AVR MCU 64K 16MHZ IND 64-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA64-16AI

• 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: 53
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Asynchronous Timer
Clock – clk
ADC Clock – clk
Clock Sources
2490Q–AVR–06/10
ASY
ADC
The Asynchronous Timer clock allows the Asynchronous Timer/Counter to be clocked directly
from an external 32 kHz clock crystal. The dedicated clock domain allows using this
Timer/Counter as a real-time counter even when the device is in sleep mode.
The ADC is provided with a dedicated clock domain. This allows halting the CPU and I/O clocks
in order to reduce noise generated by digital circuitry. This gives more accurate ADC conversion
results.
The device has the following clock source options, selectable by Flash Fuse bits as shown
below. The clock from the selected source is input to the AVR clock generator, and routed to the
appropriate modules.
Table 6. Device Clocking Options Select
Note:
The various choices for each clocking option is given in the following sections. When the CPU
wakes up from Power-down or Power-save, the selected clock source is used to time the start-
up, ensuring stable Oscillator operation before instruction execution starts. When the CPU starts
from reset, there is as an additional delay allowing the power to reach a stable level before com-
mencing normal operation. The Watchdog Oscillator is used for timing this real-time part of the
start-up time. The number of WDT Oscillator cycles used for each time-out is shown in
The frequency of the Watchdog Oscillator is voltage dependent as shown in the
acteristics” on page
Table 7. Number of Watchdog Oscillator Cycles
Device Clocking Option
External Crystal/Ceramic Resonator
External Low-frequency Crystal
External RC Oscillator
Calibrated Internal RC Oscillator
External Clock
Typ Time-out (V
1. For all fuses “1” means unprogrammed while “0” means programmed.
4.1 ms
65 ms
CC
340.
= 5.0V)
Typ Time-out (V
(1)
4.3 ms
69 ms
CC
= 3.0V)
Number of Cycles
64K (65,536)
4K (4,096)
1111 - 1010
1000 - 0101
0100 - 0001
ATmega64(L)
CKSEL3..0
1001
0000
“Typical Char-
Table
38
7.