ATmega1284P Atmel Corporation, ATmega1284P Datasheet - Page 53

• Manufacturer Part Number: ATmega1284P
• Manufacturer: Atmel Corporation

Specifications of ATmega1284P

• Flash (kbytes): 128 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 32
• Usb Speed: No
• Usb Interface: No
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 16
• Eeprom (bytes): 4096
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

11.1.4
11.1.5
8272C–AVR–06/11
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
11-5 on page
trigger level (V
out period t
The BOD circuit will only detect a drop in V
ger than t
Figure 11-5. 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
”Watchdog Timer” on page 55
Figure 11-6. Watchdog Reset During Operation
BOD
CC
TOUT
given in
53), the Brown-out Reset is immediately activated. When V
ATmega164A/PA/324A/PA/644A/PA/1284/P
BOT+
INTERNAL
TIME-OUT
has expired.
RESET
RESET
in
V
CC
Figure 11-5 on page
”System and Reset Characteristics” on page
BOT+
for details on operation of the Watchdog Timer.
= 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
53), 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
337.
HYST
CC
/2.
increases above the
TOUT
BOT-
. Refer to
in
Figure
53