Datasheet

2
7679H–CAN–08/08
AT90CAN32/64/128
1. Description
1.1 Comparison Between AT90CAN32, AT90CAN64 and AT90CAN128
AT90CAN32, AT90CAN64 and AT90CAN128 are hardware and software compatible. They dif-
fer only in memory sizes as shown in Table 1-1.
1.2 Part Description
The AT90CAN32/64/128 is a low-power CMOS 8-bit microcontroller based on the AVR
enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the
AT90CAN32/64/128 achieves throughputs approaching 1 MIPS per MHz allowing the system
designer to optimize power consumption versus processing speed.
The AVR core combines a rich instruction set with 32 general purpose working registers. All 32
registers are directly connected to the Arithmetic Logic Unit (ALU), allowing two independent
registers to be accessed in one single instruction executed in one clock cycle. The resulting
architecture is more code efficient while achieving throughputs up to ten times faster than con-
ventional CISC microcontrollers.
The AT90CAN32/64/128 provides the following features: 32K/64K/128K bytes of In-System Pro-
grammable Flash with Read-While-Write capabilities, 1K/2K/4K bytes EEPROM, 2K/4K/4K
bytes SRAM, 53 general purpose I/O lines, 32 general purpose working registers, a CAN con-
troller, Real Time Counter (RTC), four flexible Timer/Counters with compare modes and PWM, 2
USARTs, a byte oriented Two-wire Serial Interface, an 8-channel 10-bit ADC with optional differ-
ential input stage with programmable gain, a programmable Watchdog Timer with Internal
Oscillator, an SPI serial port, IEEE std. 1149.1 compliant JTAG test interface, also used for
accessing the On-chip Debug system and programming and five software selectable power sav-
ing modes.
The Idle mode stops the CPU while allowing the SRAM, Timer/Counters, SPI/CAN ports and
interrupt system to continue functioning. The Power-down mode saves the register contents but
freezes the Oscillator, disabling all other chip functions until the next interrupt or Hardware
Reset. In Power-save mode, the asynchronous timer continues to run, allowing the user to main-
tain a timer base while the rest of the device is sleeping. The ADC Noise Reduction mode stops
the CPU and all I/O modules except Asynchronous Timer and ADC, to minimize switching noise
during ADC conversions. In Standby mode, the Crystal/Resonator Oscillator is running while the
rest of the device is sleeping. This allows very fast start-up combined with low power
consumption.
The device is manufactured using Atmel’s high-density nonvolatile memory technology. The On-
chip ISP Flash allows the program memory to be reprogrammed in-system through an SPI serial
interface, by a conventional nonvolatile memory programmer, or by an On-chip Boot program
running on the AVR core. The boot program can use any interface to download the application
program in the application Flash memory. Software in the Boot Flash section will continue to run
while the Application Flash section is updated, providing true Read-While-Write operation. By
Table 1-1. Memory Size Summary
Device Flash EEPROM RAM
AT90CAN32 32K Bytes 1K Byte 2K Bytes
AT90CAN64 64K Bytes 2K Bytes 4K Bytes
AT90CAN128 128K Bytes 4K Byte 4K Bytes