ATMEGA324P-A15MZ Atmel, ATMEGA324P-A15MZ Datasheet - Page 26

• Manufacturer Part Number: ATMEGA324P-A15MZ
• Description: MCU AVR 32KB FLASH 15MHZ 44-VQFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA324P-A15MZ

• Package / Case: 44-VQFN Exposed Pad
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 32
• Eeprom Size: 1K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Program Memory Size: 32KB (32K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: I²C, SPI, UART/USART
• Core Size: 8-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Crystal Oscillator
26
ATmega32(L)
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. The CKOPT Fuse selects between two different Oscillator
amplifier modes. When CKOPT is programmed, the Oscillator output will oscillate will a full rail-
to-rail swing on the output. This mode is suitable when operating in a very noisy environment or
when the output from XTAL2 drives a second clock buffer. This mode has a wide frequency
range. When CKOPT is unprogrammed, the Oscillator has a smaller output swing. This reduces
power consumption considerably. This mode has a limited frequency range and it can not be
used to drive other clock buffers.
For resonators, the maximum frequency is 8 MHz with CKOPT unprogrammed and 16 MHz with
CKOPT programmed. 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
capacitor values given by the manufacturer should be used.
Figure 12. Crystal Oscillator Connections
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
Table 4. Crystal Oscillator Operating Modes
Note:
CKOPT
1
1
1
0
1. This option should not be used with crystals, only with ceramic resonators.
101, 110, 111
CKSEL3..1
101
110
111
(1)
Frequency Range
0.4 - 0.9
0.9 - 3.0
3.0 - 8.0
(MHz)
1.0 ≤
C2
C1
Recommended Range for Capacitors
C1 and C2 for Use with Crystals (pF)
XTAL2
XTAL1
GND
Figure
Table
12. Either a quartz crystal or a
4. For ceramic resonators, the
12 - 22
12 - 22
12 - 22
–
Table
2503N–AVR–06/08
4.