We've Got It Covered
The breadth of applications now covered by 32bit devices means IDMs are extending their reach in both directions, to make sure all use-cases are covered, as Philip Ling, Editor of ES Design magazine discovers.Ubiq
These days, ARM has focused its route to market around the Cortex range, which features three distinct families, denoted by -A, -R and -M. To differentiate these families, ARM maintains that the -A range in intended for Application Processors, the -R for processors targeting end-applications where Real-Time performance is a must, while the -M are for what is generically termed ‘embedded’, but is most often the choice for Microcontrollers.
It is the Cortex-M family that now dominates the embedded space, with almost all IDMs active in this sector offering a Cortex-M based product portfolio. The most recent large IDM to join these ranks was Infineon, who launched its first Cortex-M based product range in January 2012, the XMC4000 family, which features the -M4 core. This January, Infineon announced the XMC1000 family, which is enabled by the -M0 core.
Infineon’s target market for the XMC1000 family remains industrial control, but it claims that with this family it is breaking down the cost barrier to using 32-bit architectures, delivering it an a price comparable to the incumbent 8-bit solutions. It has achieved this largely by adopting a large-scale approach to the design and manufacture; using a leading-edge 65nm embedded Flash process on 300mm wafers. This economy of scale allows the entry-level XMC1000 products — the 1100 variants — to be brought to market at just €0.25 in volume.
The ‘high-end’ version, the 1300, is priced at €1.25 but adds a number of features, including a Field-Oriented Control (FOC) engine, which allows the parts to be used in more complex motor control applications.
Infineon's low-end XMC families
By being so aggressive with its pricing, Infineon says it overcomes the the five factors that currently inhibit 32-bit devices breaking in to low-end applications, namely: performance; peripherals; program memory; portfolio scalability, and; price. Clearly, the most influential is price, but it follows that IDMs like Infineon aren’t able to tackle the first four without pushing price up. By taking the bold step of manufacturing in high volumes or the most cost-effective process from launch, this barrier is effectively breached.
Notably, Infineon admits it isn’t targeting the ‘ultra low power’ end of the market, where Freescale and, more recently NXP, have launched devices based on the ‘slimmed down’ Cortex-M0+ core, stating that it wouldn’t have brought any benefits to the XMC1000 family.
While Infineon builds its portfolio by adding low-end devices, Atmel has just released details of its latest SAM family which features a Cortex-A5 core. This is ARM’s ‘entry-level’ Application Processor core and as such is not normally deployed in what is essentially a microcontroller family. However, the -A family is better placed to offer a migration path for code previously deployed on ARM’s ARM9 and ARM11 architectures and as such may find favour in the embedded space. As stated, the Cortex-A5 is ARM’s ‘entry level’ Application Processor core, but Atmel claims it matches or even surpasses the Cortex-A8 in many areas.
The more capable core means the SAMA5D3 is able to take on more demanding operating systems not normally deployed on microcontrollers, which includes Android 4.0. Atmel intends to make a port of this and Linux available, via www.at91.com/android4sam and www.linux4sam.com respectively.
One of the key application areas for the SAMA5D3 will, like Infineon’s XMC, be the industrial sector, where faster connectivity is cited as one of the drivers for more processing performance. It’s also being manufactured on a 65nm process.
Both Atmel and Infineon identify security as an important feature of their respective new product lines. The SAMA5D3 features a secure boot loader and a hardware encryption engine with AES, along with 3DES and SHA support to encrypt/decrypt data or communications. A true random number generator is also included for generating unique keys.
Atmel's newest high-end family
The XMC1000 also uses AES and in this case Infineon is developing a method of using it to encrypt the software embedded at the factory, using a key that is limited to a certain number of MCUs. While relatively straightforward in concept, Infineon stated it is still working out the logistics of the approach.
There’s still a growing number of ARM-based MCUs entering the embedded market on an almost daily basis, and for a long time the ‘sweet spot’ in performance was served by the Cortex-M3. More recently the focus has moved to ultra-low-power and for this the Cortex-M0+ is emerging as the preferred choice. It’s refreshing, therefore, to see two new families that appear to defy these trends, particularly with the use of a Cortex-A5 in an MCU-type family. Could this signal a new age of embedded processing and put even more pressure on the venerable 8-bit architectures? Infineon certainly seems to believe so, stating that it sees ‘no future’ for 8-bit and that it is focusing all of its development on 32-bit architectures.