ATMEGA169V-1MC Atmel, ATMEGA169V-1MC Datasheet - Page 42

• Manufacturer Part Number: ATMEGA169V-1MC
• Description: IC MCU AVR 16K 1.8V 1MHZ 64-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA169V-1MC

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 1MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 64-MLF®, 64-QFN
• For Use With: ATAVRISP2 - PROGRAMMER AVR IN SYSTEMATAVRBFLY - KIT EVALUATION AVR BUTTERFLYATSTK502 - MOD EXPANSION AVR STARTER 500
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Watchdog Timer
42
ATmega169V/L
The Watchdog Timer is clocked from a separate On-chip Oscillator which runs at
1 MHz. This is the typical value at V
at other V
interval can be adjusted as shown in Table 21 on page 43. The WDR – Watchdog Reset
– instruction resets the Watchdog Timer. The Watchdog Timer is also reset when it is
disabled and when a Chip Reset occurs. Eight different clock cycle periods can be
selected to determine the reset period. If the reset period expires without another
Watchdog Reset, the ATmega169 resets and executes from the Reset Vector. For tim-
ing details on the Watchdog Reset, refer to Table 21 on page 43.
To prevent unintentional disabling of the Watchdog or unintentional change of time-out
period, two different safety levels are selected by the fuse WDTON as shown in Table
20. Refer to “Timed Sequences for Changing the Configuration of the Watchdog Timer”
on page 44 for details.
Table 20. WDT Configuration as a Function of the Fuse Settings of WDTON
Figure 20. Watchdog Timer
WDTON
Unprogrammed
Programmed
CC
levels. By controlling the Watchdog Timer prescaler, the Watchdog Reset
Safety
Level
1
2
OSCILLATOR
WATCHDOG
WDT Initial
State
Disabled
Enabled
CC
= 5V. See characterization data for typical values
How to Disable the
WDT
Timed sequence
Always enabled
How to Change
Time-out
Timed sequence
Timed sequence
2514H–AVR–05/03