AT90CAN64-16AUR Atmel, AT90CAN64-16AUR Datasheet - Page 42

• Manufacturer Part Number: AT90CAN64-16AUR
• Description: MCU AVR 64K FLASH 16MHZ 64TQFP
• Manufacturer: Atmel
• Series: AVR® 90CANr

Specifications of AT90CAN64-16AUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: CAN, EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

5.6.1
5.7
42
External Clock
AT90CAN32/64/128
Oscillator Calibration Register – OSCCAL
When this Oscillator is selected, start-up times are determined by the SUT Fuses as shown in
Table
Table 5-8.
Note:
• Bit 7 – Reserved Bit
This bit is reserved for future use.
• Bits 6..0 – CAL6..0: Oscillator Calibration Value
Writing the calibration byte to this address will trim the internal Oscillator to remove process vari-
ations from the Oscillator frequency. This is done automatically during Chip Reset. When
OSCCAL is zero, the lowest available frequency is chosen. Writing non-zero values to this regis-
ter will increase the frequency of the internal Oscillator. Writing 0x7F to the register gives the
highest available frequency. The calibrated Oscillator is used to time EEPROM and Flash
access. If EEPROM or Flash is written, do not calibrate to more than 10% above the nominal fre-
quency. Otherwise, the EEPROM or Flash write may fail. Note that the Oscillator is intended for
calibration to 8.0 MHz. Tuning to other values is not guaranteed, as indicated in
Table 5-9.
To drive the device from an external clock source, XTAL1 should be driven as shown in
5-4. To run the device on an external clock, the CKSEL Fuses must be programmed to “0000”.
Bit
Read/Write
Initial Value
SUT1..0
OSCCAL Value
10
00
01
11
(1)
5-8.
0x3F
0x7F
0x00
1. The device is shipped with this option selected.
Start-up Time from Power-
Start-up times for the internal calibrated RC Oscillator clock selection
Internal RC Oscillator Frequency Range.
R
7
–
0
down and Power-save
CAL6
Min Frequency in Percentage of
R/W
6
<----- -----------
6 CK
6 CK
6 CK
Nominal Frequency
CAL5
R/W
5
100%
50%
75%
Device Specific Calibration Value
CAL4
R/W
4
Additional Delay from
CAL3
Reset (V
R/W
3
Reserved
14 CK + 4.1 ms
14 CK + 65 ms
14 CK
CAL2
CC
R/W
2
= 5.0V)
Max Frequency in Percentage of
CAL1
----------- ----->
R/W
1
Nominal Frequency
Recommended Usage
BOD enabled
Fast rising power
Slowly rising power
CAL0
R/W
0
100%
150%
200%
OSCCAL
Table
7679H–CAN–08/08
5-9.
Figure