AT90CAN32 Automotive Atmel Corporation, AT90CAN32 Automotive Datasheet - Page 38

• Manufacturer Part Number: AT90CAN32 Automotive
• Manufacturer: Atmel Corporation

Specifications of AT90CAN32 Automotive

• Flash (kbytes): 32 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 53
• Ext Interrupts: 8
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 2
• Can: 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: No
• Crypto Engine: No
• Sram (kbytes): 2
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• 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: 4
• Output Compare Channels: 8
• Input Capture Channels: 2
• Pwm Channels: 7
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

5.1.4
5.1.5
5.2
5.3
38
Clock Sources
Default Clock Source
AT90CAN32/64/128
Asynchronous Timer Clock – clk
ADC Clock – clk
The Asynchronous Timer clock allows the Asynchronous Timer/Counter to be clocked directly
from an external clock or an external 32 kHz clock crystal. The dedicated clock domain allows
using this Timer/Counter as a real-time counter even when the device is in sleep mode.
The ADC is provided with a dedicated clock domain. This allows halting the CPU and I/O clocks
in order to reduce noise generated by digital circuitry. This gives more accurate ADC conversion
results.
The device has the following clock source options, selectable by Flash Fuse bits as shown
below. The clock from the selected source is input to the AVR clock generator, and routed to the
appropriate modules.
Table 5-1.
Note:
The various choices for each clocking option is given in the following sections. When the CPU
wakes up from Power-down or Power-save, the selected clock source is used to time the start-
up, ensuring stable Oscillator operation before instruction execution starts. When the CPU starts
from reset, there is an additional delay allowing the power to reach a stable level before starting
normal operation. The Watchdog Oscillator is used for timing this real-time part of the start-up
time. The number of WDT Oscillator cycles used for each time-out is shown in
frequency of the Watchdog Oscillator is voltage dependent as shown in
Typical Characteristics” on page
Table 5-2.
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.
Device Clocking Option
External Crystal/Ceramic Resonator
External Low-frequency Crystal
Calibrated Internal RC Oscillator
External Clock
Reserved
ADC
Typ Time-out (V
1. For all fuses “1” means unprogrammed while “0” means programmed.
4.1 ms
65 ms
Device Clocking Options Select
Number of Watchdog Oscillator Cycles
ASY
CC
= 5.0V)
383.
Typ Time-out (V
(1)
4.3 ms
69 ms
CC
= 3.0V)
Number of Cycles
“AT90CAN32/64/128
64K (65,536)
4K (4,096)
0111 - 0100
1111 - 1000
0011, 0001
CKSEL3..0
0010
0000
Table
7682C–AUTO–04/08
5-2. The