ATMEGA324PA-MCHR Atmel, ATMEGA324PA-MCHR Datasheet - Page 54

• Manufacturer Part Number: ATMEGA324PA-MCHR
• Description: MCU AVR 32KB FLASH 20 MHZ 44QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA324PA-MCHR

• 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: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K 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: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10.1.4
10.1.5
8152G–AVR–11/09
Brown-out Detection
Watchdog Reset
ATmega164PA/324PA/644PA/1284P has an On-chip Brown-out Detection (BOD) circuit for
monitoring the V
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 inter-
preted 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
for details on operation of the Watchdog Timer.
BOD
CC
TOUT
BOT+
given in
54), the Brown-out Reset is immediately activated. When V
BOT+
INTERNAL
TIME-OUT
has expired.
CC
= V
RESET
RESET
level during operation by comparing it to a fixed trigger level. The trigger level
in
BOT
V
CC
Figure 10-5 on page
”System and Reset Characteristics” on page
+ V
HYST
ATmega164PA/324PA/644PA/1284P
/2 and V
CC
decreases to a value below the trigger level (V
V
CK
BOT-
BOT-
54), the delay counter starts the MCU after the Time-
CC
= V
if the voltage stays below the trigger level for lon-
BOT
- V
HYST
/2.
V
t
TOUT
BOT+
334.
CC
increases above the
TOUT
BOT-
. Refer to
in
Figure
54