PLC and I/O Modules

PLC systems are highly complex, integrating numerous board modules to cover the multiple needs of modern automated industrial environments. They include:

• Programmable logic controllers (PLC) or programmable automated controllers (PAC)
• Distributed Control Systems
• Digital and analog IO-modules
• Field bus communication modules
• Industrial Ethernet interfaces
• Wireless communication module

The diversity of board designs for industrial PLC applications is challenging for R&D departments. For optimal hardware and software development, designers need a broad, efficient product family where development can be re-used as much as possible. To meet these needs, Atmel® offers efficient AVR® family and ARM-based product lines ranging from low pincount, low flash size microcontrollers to high-performing embedded MPUs running at 400MHz. Additionally, some PLC systems require certification, especially where safety and environment are a chief concern. In these cases, the use of counterfeit components in systems presents substantial liability exposure. Embedding an Atmel secure authentication product helps minimize these concerns.

Features and Benefits

For Main CPU Applications:

• The Atmel AT91SAM9 family offers up to 400Mhz ARM926EJ core with up to 32KB instruction and data caches for fast execution times.
• Unique dual EBI (External Bus interface) feature allows connecting dedicated circuits for field bus or real time industrial Ethernet communication without strongly impacting the bus load and the performance of the application.
• The implementation of the TCM (Tightly Coupled Memory) interface on selected products enables access to the internal SRAM with zero wait state at 400MHz. With this feature, time-critical code sections and interrupt routines can be executed fast and deterministically.
• Atmel microcontrollers support up to 37 DMA channels with double buffering feature to minimize CPU load and reduce real time constraints.
• Support of the DDR2 external memory enables lower cost and longer availability for CPU devices.
• Integrated Power-on-Reset and the simplified power sequence remove the need of cost-intensive external power management IC.
• Serial NVM, such as serial data flash or in SD-card, for system boot, allows small PCB layout.
• Industrial BGA package with 0.8mm pitch eases PCB layout and reduce assembly costs.
• Atmel provides system security solutions as peripheral components to offer the flexibility of optional inclusion and low cost.

For IO module solutions:

• High-speed serial peripherals for a fast communication with backplane bus interface or the connection to high resolution external ADC or DAC, with SPI data rates up to 48Mbps on the AT91SAM3U. CAN modules are available on Atmel AVR UC3, megaAVR and AT91SAM microcontrollers.
• Numerous 16-bit timers with input capture function for time stamping.
• PWM channels support control and dim functions for LEDs.
• Atmel supports a rich set of analog functions such as 12-bit ADC and DAC, as well as analog comparator for monitoring the operation condition of the IO-module.
• Safety functions ease the implementation of Safety Integrity Levels (SIL) IEC61508 standard.
• High performance CPU up to 96MHz with integrated MAC unit supports the growing demand for signal conditioning on the analog IO-module.

PLC and IO Devices

• Main CPU applications can utilize the Atmel AT91SAM9 family, which enables developers to reduce the cost of the main CPU board without compromising on the system performance and functionality.
• IO modules (digital, analog or safety module) have a variety of requirements, depending on the product. The Atmel AVR and AT91SAM microcontroller families offer diverse package, flash size, and peripheral sets to meet a range of needs.

The Atmel AT91SAM9 family in the main CPU board provides a unique combination of high deterministic performance and optimized system cost and space utilization. Numerous high-speed serial communication peripherals enable fast PLC internal communications.

Product Families

	Type	Recommended Microcontroller	Key benefit	Hardware Authentication	Non Volatile Memory	Touch
PLC	Compact - low end	ARM-based Solutions: - AT91SAM3S AVR UC3 32-bit microcontrollers	Flash size up to 512KB, optional Ethernet MAC & CAN included	AT88SA102S AT88SA10HS	Serial EEPROM	Buttons, Sliders and Wheels QTouch Library maXTouch Touchscreen controller
	Mid-range	ARM-based Solutions: - AT91SAM9G20 - AT91SAM9G45	Up to 400MHz, deterministic behavior	AT88SA102S AT88SA10HS	Serial EEPROM Serial Flash Dataflash
	High-end	AT91CAP	ARM SoC expertise
IO-Modules	Digital IO	AVR XMEGA ARM-based Solutions: - AT91SAM3N AVR UC3 B Series 32-bit microcontrollers	high speed peripherals and timers	AT88SA102S AT88SA10HS	Serial EEPROM
	Analog IO	ARM-based Solutions: - AT91SAM3S AVR UC3 B Series 32-bit microcontrollers	Additional signal processing capabilities	AT88SA102S AT88SA10HS
	Safety IO	AVR XMEGA ARM-based Solutions: - AT91SAM3S	dedicated hardware safety function	AT88SA102S AT88SA10HS

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