ATMEGA32M1-MU Atmel, ATMEGA32M1-MU Datasheet - Page 29

• Manufacturer Part Number: ATMEGA32M1-MU
• Description: MPU AVR 32K FLASH 20MHZ 32-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32M1-MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: CAN, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• 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): 2.7 V ~ 5.5 V
• Data Converters: A/D 11x10b; D/A 1x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Number Of I /o: -

8.3
8.4
8209D–AVR–11/10
Default Clock Source
Low Power Crystal Oscillator
Table 8-2.
The device is shipped with CKSEL = “0010”, SUT = “10”, and CKDIV8 programmed. The default
clock source setting is the Internal RC Oscillator with longest start-up time and an initial system
clock prescaling of 8. This default setting ensures that all users can make their desired clock
source setting using an In-System or Parallel programmer.
XTAL1 and XTAL2 are input and output, respectively, of an inverting amplifier which can be con-
figured for use as an On-chip Oscillator, as shown in
ceramic resonator may be used.
This Crystal Oscillator is a low power oscillator, with reduced voltage swing on the XTAL2 out-
put. It gives the lowest power consumption, but is not capable of driving other clock inputs.
C1 and C2 should always be equal for both crystals and resonators. The optimal value of the
capacitors depends on the crystal or resonator in use, the amount of stray capacitance, and the
electromagnetic noise of the environment. Some initial guidelines for choosing capacitors for
use with crystals are given in
ues given by the manufacturer should be used. For more information on how to choose
capacitors and other details on Oscillator operation, refer to the Multi-purpose Oscillator Applica-
tion Note.
Figure 8-2.
The Oscillator can operate in three different modes, each optimized for a specific frequency
range. The operating mode is selected by the fuses CKSEL3..1 as shown in
30.
Typ Time-out (V
4.1ms
65ms
Number of Watchdog Oscillator Cycles
Crystal Oscillator Connections
CC
= 5.0V)
Table 8-3 on page
Typ Time-out (V
C2
C1
ATmega16M1/32M1/64M1
4.3ms
69ms
30. For ceramic resonators, the capacitor val-
CC
= 3.0V)
Figure
XTAL2
XTAL1
GND
8-2. Either a quartz crystal or a
Number of Cycles
64K (65,536)
4K (4,096)
Table 8-3 on page
29