AT90S4434-8JI Atmel, AT90S4434-8JI Datasheet - Page 5

• Manufacturer Part Number: AT90S4434-8JI
• Description: IC MCU 4K 8MHZ A/D IT 44PLCC
• Manufacturer: Atmel
• Series: AVR® 90Sr

Specifications of AT90S4434-8JI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-PLCC
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Architectural Overview
The fast-access register file concept contains 32 x 8-bit general-purpose working registers with a single clock cycle access
time. This means that during one single clock cycle, one Arithmetic Logic Unit (ALU) operation is executed. Two operands
are output from the register file, the operation is executed and the result is stored back in the register file – in one clock
cycle.
Six of the 32 registers can be used as three 16-bit indirect address register pointers for Data Space addressing, enabling
efficient address calculations. One of the three address pointers is also used as the address pointer for the constant table
look-up function. These added function registers are the 16-bit X-register, Y-register and Z-register.
Figure 2. The AT90S4434/8535 AVR RISC Architecture
The ALU supports arithmetic and logic functions between registers or between a constant and a register. Single register
operations are also executed in the ALU. Figure 2 shows the AT90S4434/8535 AVR RISC microcontroller architecture.
In addition to the register operation, the conventional memory addressing modes can be used on the register file as well.
This is enabled by the fact that the register file is assigned the 32 lowermost Data Space addresses ($00 - $1F), allowing
them to be accessed as though they were ordinary memory locations.
Control Lines
2K/4K X 16
Instruction
Instruction
Program
Register
Decoder
Memory
AVR AT90S4434/8535 Architecture
Program
Counter
and Control
256/512 x 8
256/512 x 8
Registrers
EEPROM
I/O Lines
Purpose
General
Data Bus 8-bit
SRAM
Status
32 x 8
Data
ALU
32
Analog to Digital
Timer/Counter
Timer/Counter
Timer/Counter
Comparator
with PWM
with PWM
Watchdog
Converter
Interrupt
Analog
UART
Serial
Timer
16-bit
8-bit
8-bit
Unit
Unit
SPI
5