1
Pin Configurations
TQFP Top View
PDIP
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
(INT1) PD3
(T0) PD4
NC
VCC
GND
NC
XTAL1
XTAL2
PC1 (ADC1)
PC0 (ADC0)
NC
AGND
AREF
NC
AVCC
PB5 (SCK)
32
31
30
29
28
27
26
25
9
10
11
12
13
14
15
16
(T1) PD5
(AIN0) PD6
(AIN1) PD7
(ICP) PB0
(OC1) PB1
(SS) PB2
(MOS1) PB3
(MOS0) PB4
PD2 (INT0)
PD1 (TXD)
PD0 (RDX)
RESET
PC5 (ADC5)
PC4 (ADC4)
PC3 (ADC3)
PC2 (ADC2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
RESET
(RXD) PD0
(TXD) PD1
(INT0) PD2
(INT1) PD3
(T0) PD4
VCC
GND
XTAL1
XTAL2
(T1) PD5
(AIN0) PD6
(AIN1) PD7
(ICP) PB0
PC5 (ADC5)
PC4 (ADC4)
PC3 (ADC3)
PC2 (ADC2)
PC1 (ADC1)
PC0 (ADC0)
AGND
AREF
AVCC
PB5 (SCK)
PB4 (MISO)
PB3 (MOSI)
PB2 (SS)
PB1 (OC1)
Features
High-performance and Low-power AVR
8-bit RISC Architecture
118 Powerful Instructions - Most Single Cycle Execution
32 x 8 General Purpose Working Registers
Up to 8 MIPS Throughput at 8 MHz
Data and Nonvolatile Program Memory
2K/4K Bytes of In-System Programmable Flash
Endurance 1,000 Write/Erase Cycles
128 Bytes of SRAM
128/256 Bytes of In-System Programmable EEPROM
Endurance: 100,000 Write/Erase Cycles
Programming Lock for Flash Program and EEPROM Data Security
Peripheral Features
One 8-bit Timer/Counter with Separate Prescaler
Expanded 16-bit Timer/Counter with Separate Prescaler,
Compare, Capture Modes and 8-, 9- or 10-bit PWM
On-chip Analog Comparator
Programmable Watchdog Timer with Separate On-chip Oscillator
Programmable UART
6-channel, 10-bit ADC
Master/Slave SPI Serial Interface
Special Microcontroller Features
Brown-Out Reset Circuit
Enhanced Power-on Reset Circuit
Low-Power Idle and Power Down Modes
External and Internal Interrupt Sources
Specifications
Low-power, High-speed CMOS Process Technology
Fully Static Operation
Power Consumption at 4 MHz, 3V, 25
C
Active: 3.4 mA
Idle Mode: 1.4 mA
Power Down Mode: <1 A
I/O and Packages
20 Programmable I/O Lines
28-pin PDIP and 32-pin TQFP
Operating Voltage
2.7V - 6.0V (AT90LS2333 and AT90LS4433)
4.0V - 6.0V (AT90S2333 and AT90S4433)
Speed Grades
0 - 4 MHz (AT90LS2333 and AT90LS4433)
0 - 8 MHz (AT90S2333 and AT90S4433)
Rev. 1042DS04/99
8-bit
Microcontroller
with 2K/4K bytes
In-System
Programmable
Flash
AT90S2333
AT90LS2333
AT90S4433
AT90LS4433
Preliminary
Note: This is a summary document. For the complete 103 page
document, please visit our Web site at www.atmel.com or e-mail
at literature@atmel.com and request literature #1042D.
AT90S/LS2333 and AT90S/LS4433
2
Description
The AT90S2333/4433 is a low-power CMOS 8-bit microcontroller based on the AVR RISC architecture. By executing pow-
erful instructions in a single clock cycle, the AT90S2333/4433 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 the 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 conventional CISC microcontrollers.
The AT90S2333/4433 provides the following features: 2K/4K bytes of In-System Programmable Flash, 128/256 bytes
EEPROM, 128 bytes SRAM, 20 general purpose I/O lines, 32 general purpose working registers, two flexible
timer/counters with compare modes, internal and external interrupts, a programmable serial UART, 6-channel, 10-bit ADC,
programmable Watchdog Timer with internal oscillator, an SPI serial port and two software selectable power saving modes.
The Idle mode stops the CPU while allowing the SRAM, timer/counters, SPI port and interrupt system to continue function-
ing. The Power Down mode saves the register contents but freezes the oscillator, disabling all other chip functions until the
next interrupt or hardware reset.
The device is manufactured using Atmel's high density nonvolatile memory technology. The on-chip Flash program mem-
ory can be reprogrammed in-system through an SPI serial interface or by a conventional nonvolatile memory programmer.
By combining a RISC 8-bit CPU with In-System Programmable Flash on a monolithic chip, the Atmel AT90S2333/4433 is a
powerful microcontroller that provides a highly flexible and cost effective solution to many embedded control applications.
The AT90S2333/4433 AVR is supported with a full suite of program and system development tools including: C compilers,
macro assemblers, program debugger/simulators, in-circuit emulators, and evaluation kits.
Table 1. Comparison Table
Device
Flash
EEPROM
SRAM
Voltage Range
Frequency
AT90S2333
2K
128B
128B
4.0V - 6.0V
0 - 8 MHz
AT90LS2333
2K
128B
128B
2.7V - 6.0V
0 - 4 MHz
AT90S4433
4K
256B
128B
4.0V - 6.0V
0 - 8 MHz
AT90LS4433
4K
256B
128B
2.7V - 6.0V
0 - 4 MHz
AT90S/LS2333 and AT90S/LS4433
3
Block Diagram
Figure 1. The AT90S2333/4433 Block Diagram
PROGRAM
COUNTER
INTERNAL
OSCILLATOR
WATCHDOG
TIMER
STACK
POINTER
PROGRAM
FLASH
MCU CONTROL
REGISTER
SRAM
GENERAL
PURPOSE
REGISTERS
INSTRUCTION
REGISTER
TIMER/
COUNTERS
INSTRUCTION
DECODER
DATA DIR.
REG. PORTB
DATA DIR.
REG. PORTC
DATA REGISTER
PORTB
DATA REGISTER
PORTC
ANALOG MUX
ADC
DATA REGISTER
PORTD
PROGRAMMING
LOGIC
TIMING AND
CONTROL
OSCILLATOR
INTERRUPT
UNIT
EEPROM
SPI
UART
STATUS
REGISTER
Z
Y
X
ALU
PORTB DRIVERS
PORTC DRIVERS
PORTD DRIVERS
PB0 - PB5
PC0 - PC5
RESET
VCC
AVCC
AGND
AREF
GND
XTAL2
XTAL1
CONTROL
LINES
+
-
ANALOG
COMPARATOR
PD0 - PD7
8-BIT DATA BUS
DATA DIR.
REG. PORTD
AT90S/LS2333 and AT90S/LS4433
4
Pin Descriptions
VCC
Supply voltage
GND
Ground
Port B (PB5..PB0)
Port B is a 6-bit bi-directional I/O port with internal pullup resistors. The Port B output buffers can sink 20 mA. As inputs,
Port B pins that are externally pulled low will source current if the pull-up resistors are activated.
Port B also serves the functions of various special features of the AT90S2333/4433.
The port B pins are tristated when a reset condition becomes active, even if the clock is not running.
Port C (PC5..PC0)
Port C is a 6-bit bi-directional I/O port with internal pullup resistors. The Port C output buffers can sink 20 mA. As inputs,
Port C pins that are externally pulled low will source current if the pull-up resistors are activated. Port C also serves as the
analog inputs to the A/D Converter.
The port C pins are tristated when a reset condition becomes active, even if the clock is not running.
Port D (PD7..PD0)
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors. The Port D output buffers can sink 20 mA. As inputs,
Port D pins that are externally pulled low will source current if the pull-up resistors are activated.
Port D also serves the functions of various special features of the AT90S2333/4433.
The port D pins are tristated when a reset condition becomes active, even if the clock is not running.
RESET
Reset input. An external reset is generated by a low level on the RESET pin. Reset pulses longer than 50 ns will generate
a reset, even if the clock is not running. Shorter pulses are not guaranteed to generate a reset.
XTAL1
Input to the inverting oscillator amplifier and input to the internal clock operating circuit.
XTAL2
Output from the inverting oscillator amplifier
AVCC
This is the supply voltage pin for the A/D Converter. It should be externally connected to V
CC
via a low-pass filter. See
Datasheet for details on operation of the ADC.
AREF
This is the analog reference input for the A/D Converter. For ADC operations, a voltage in the range 2.7V to AVCC must be
applied to this pin.
AGND
If the board has a separate analog ground plane, this pin should be connected to this ground plane. Otherwise, connect to
GND.
AT90S/LS2333 and AT90S/LS4433
5
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-bits 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-bits X-register, Y-register and Z-register.
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 AT90S2333/4433 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.
Figure 2. The AT90S2333/4433 AVR RISC Architecture
1K/2K X 16
Program
Memory
Instruction
Register
Instruction
Decoder
Program
Counter
Control Lines
32 x 8
General
Purpose
Registrers
ALU
Status
and Control
Interrupt
Unit
SPI
Unit
8-bit
Timer/Counter
Watchdog
Timer
Analog to Digital
Converter
Analog
Comparator
20
I/O Lines
128/256 x 8
EEPROM
Data Bus 8-bit
AVR
AT90S2333/4433 Architecture
Serial
UART
16-bit
Timer/Counter
with PWM
128 x 8
Data
SRAM
Direct Addressing
Indirect Addressing
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