ATMEGA1284P-MUR Atmel, ATMEGA1284P-MUR Datasheet - Page 54

• Manufacturer Part Number: ATMEGA1284P-MUR
• Description: MCU AVR 128KB FLASH 20MHZ 44VQFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA1284P-MUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 128KB (64K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VQFN Exposed Pad
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10.1.4
10.1.5
8272A–AVR–01/10
Brown-out Detection
Watchdog Reset
ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P has an On-chip Brown-out Detec-
tion (BOD) circuit for monitoring the V
level. The trigger level for the BOD can be selected by the BODLEVEL Fuses. The trigger level
has a hysteresis to ensure spike free Brown-out Detection. The hysteresis on the detection level
should be interpreted as V
When the BOD is enabled, and V
10-5 on page
trigger level (V
out period t
The BOD circuit will only detect a drop in V
ger than t
Figure 10-5. Brown-out Reset During Operation
When the Watchdog times out, it will generate a short reset pulse of one CK cycle duration. On
the falling edge of this pulse, the delay timer starts counting the Time-out period t
page 62
Figure 10-6. Watchdog Reset During Operation
164A/164PA/324A/324PA/644A/644PA/1284/1284P
for details on operation of the Watchdog Timer.
BOD
CC
TOUT
given in
54), the Brown-out Reset is immediately activated. When V
BOT+
INTERNAL
TIME-OUT
has expired.
RESET
RESET
in
V
CC
Figure 10-5 on page
”System and Reset Characteristics” on page
BOT+
= V
CC
BOT
decreases to a value below the trigger level (V
CC
V
CK
+ V
BOT-
level during operation by comparing it to a fixed trigger
HYST
54), the delay counter starts the MCU after the Time-
CC
/2 and V
if the voltage stays below the trigger level for lon-
BOT-
= V
V
t
TOUT
BOT
BOT+
- V
335.
HYST
CC
/2.
increases above the
TOUT
BOT-
. Refer to
in
Figure
54