AT90CAN128-15AZ Atmel, AT90CAN128-15AZ Datasheet - Page 58

• Manufacturer Part Number: AT90CAN128-15AZ
• Description: MCU AVR 128K FLASH 15MHZ 64TQFP
• Manufacturer: Atmel
• Series: AVR® 90CANr

Specifications of AT90CAN128-15AZ

• Package / Case: 64-TQFP, 64-VQFP
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 53
• Eeprom Size: 4K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 4K x 8
• Program Memory Size: 128KB (128K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: CAN, I²C, SPI, UART/USART
• Core Size: 8-Bit
• Processor Series: AT90CANx
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: CAN, SPI, UART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 53
• Number Of Timers: 4
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATDVK90CAN1, ATADAPCAN01
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Cpu Family: 90C
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 16MHz
• Total Internal Ram Size: 4KB
• # I/os (max): 53
• Number Of Timers - General Purpose: 4
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 64
• Package Type: TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.3.1
58
AT90CAN32/64/128
Watchdog Timer Control Register – WDTCR
• Bits 7..5 – Reserved Bits
These bits are reserved bits for future use.
• Bit 4 – WDCE: Watchdog Change Enable
This bit must be set when the WDE bit is written to logic zero. Otherwise, the Watchdog will not
be disabled. Once written to one, hardware will clear this bit after four clock cycles. Refer to the
description of the WDE bit for a Watchdog disable procedure. This bit must also be set when
changing the prescaler bits.
Watchdog Timer” on page 59.
• Bit 3 – WDE: Watchdog Enable
When the WDE is written to logic one, the Watchdog Timer is enabled, and if the WDE is written
to logic zero, the Watchdog Timer function is disabled. WDE can only be cleared if the WDCE bit
has logic level one. To disable an enabled Watchdog Timer, the following procedure must be
followed:
In safety level 2, it is not possible to disable the Watchdog Timer, even with the algorithm
described above.
Timer” on page 59.
• Bits 2..0 – WDP2, WDP1, WDP0: Watchdog Timer Prescaler 2, 1, and 0
The WDP2, WDP1, and WDP0 bits determine the Watchdog Timer prescaling when the Watch-
dog Timer is enabled. The different prescaling values and their corresponding Timeout Periods
are shown in
Table 7-6.
1. In the same operation, write a logic one to WDCE and WDE. A logic one must be writ-
2. Within the next four clock cycles, write a logic 0 to WDE. This disables the Watchdog.
WDP2
Initial Value
Read/Write
0
0
0
0
1
1
1
1
Bit
ten to WDE even though it is set to one before the disable operation starts.
WDP1
Table
0
0
1
1
0
0
1
1
Watchdog Timer Prescale Select
R
7
–
0
See “Timed Sequences for Changing the Configuration of the Watchdog
7-6.
WDP0
0
1
0
1
0
1
0
1
R
6
–
0
See “Timed Sequences for Changing the Configuration of the
Oscillator Cycles
R
5
–
0
Number of WDT
32/64K cycles
1,024K cycles
2,048K cycles
256K cycles
512K cycles
16K cycles
32K cycles
64K cycles
WDCE
R/W
0
4
WDE
R/W
3
0
Typical Time-out at
WDP2
R/W
2
0
V
CC
17.1 ms
34.3 ms
68.5 ms
0.14 s
0.27 s
0.55 s
1.1 s
2.2 s
= 3.0V
WDP1
R/W
1
0
WDP0
R/W
0
0
Typical Time-out at
WDTCR
V
CC
16.3 ms
32.5 ms
7679H–CAN–08/08
65 ms
0.13 s
0.26 s
0.52 s
1.0 s
2.1 s
= 5.0V