ATmega328P Automotive Atmel Corporation, ATmega328P Automotive Datasheet - Page 31

• Manufacturer Part Number: ATmega328P Automotive
• Manufacturer: Atmel Corporation

Specifications of ATmega328P Automotive

• Flash (kbytes): 32 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 24
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• 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: Yes
• Crypto Engine: No
• Sram (kbytes): 2
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 125
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 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

8.5
7810A–AVR–11/09
Low Frequency Crystal Oscillator
The Low-frequency Crystal Oscillator is optimized for use with a 32.768 kHz watch crystal.
When selecting crystals, load capasitance and crystal’s Equivalent Series Resistance, ESR
must be taken into consideration. Both values are specified by the crystal vendor. ATmega328P
oscillator is optimized for very low power consumption, and thus when selecting crystals, see
Table 8-7 on page 31
crystals
Table 8-7.
Note:
The Low-frequency Crystal Oscillator provides an internal load capacitance of typical 6 pF at
each TOSC pin. The external capacitance (C) needed at each TOSC pin can be calculated by
using:
where CL is the load capacitance for a 32.768 kHz crystal specified by the crystal vendor and C
is the total stray capacitance for one TOSC pin.
Crystals specifying load capacitance (CL) higher than 6 pF, require external capacitors applied
as described in
The Low-frequency Crystal Oscillator must be selected by setting the CKSEL Fuses to “0110” or
“0111”, as shown in
Table
Table 8-8.
Table 8-9.
Note:
C
CKSEL3..0
=
SUT1..0
0100
0101
2
00
01
10
11
8-8.
(1)
1. Maximum ESR is typical value based on characterization
1. This option should only be used if frequency stability at start-up is not important for the
CL C
application
–
Maximum ESR Recommendation for 32.768 kHz Crystal
S
Start-up Times for the Low-frequency Crystal Oscillator Clock Selection
Start-up Times for the Low-frequency Crystal Oscillator Clock Selection
Additional Delay from Reset (V
Figure 8-2 on page
Crystal CL (pF)
Power-down and Power-save
Table
12.5
6.5
9.0
for maximum ESR recommendations on 6.5 pF, 9.0 pF and 12.5 pF
Start-up Time from
8-9. Start-up times are determined by the SUT Fuses as shown in
4 CK + 4.1 ms
4 CK + 65 ms
32K CK
1K CK
4 CK
28.
ATmega328P [Preliminary]
CC
= 5.0V) Recommended Usage
Reserved
Fast rising power or BOD enabled
Slowly rising power
Stable frequency at start-up
Recommended Usage
Stable frequency at start-up
Max ESR [k ]
75
65
30
(1)
31
S