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pulse embodied in the analogue loop – and perhaps only 25% of the capacity of the core might be taken up. If you add a PMBus protocol stack to communicate with the digital power bus, that might use 50% of the core’s time; but there would still be the capability to implement, for example, a watchdog routine. There is, however, no facility (or the computational resource) to carry out an auto-compensation routine; as is normal for an analogue regulator, the designer will have to establish the correct loop compensation to achieve stable and responsive behaviour. Once the correct loop filter values have been determined, however, the on-chip microcontroller selects the appropriate R and C values from on-chip arrays: no external parts are needed, and the same base part can be set up with many different values for different applications. Microchip has been developing its own power output FETs and has released new parts to accompany the 19111 – although the part will drive FETs from other sources. MCP87018, MCP87030, MCP87090 and MCP87130 are high-speed 1.8 mΩ, 3 mΩ, 9 mΩ and 13 mΩ logic-level MOSFETs rated at 25V. Microchip claims a very low (good) figure-of-merit of on-resistance-timesgate charge; the company notes that, with both controller and MOSFET technology in-house, higher-integration solutions such as multi-FET arrays on a single substrate are a possibility, and Microchip’s designers will explore such options as market need dictates. An MCP19111 Evaluation Board (ADM00397) is priced at $49.99 and also includes Microchip’s high-speed MOSFETs. It comes with standard firmware, which is user-configurable through an MPLAB X IDE Graphical User Interface (GUI) plug-in. The MCP19111 will cost $2.81 (5000); volume pricing for the FETs ranges from $0.29 to $1.04. - by Graham Prophet Microchip, www.microchip.com/MCP19111 Tanner offers open-access for EDA tool suite Tanner EDA, popular as a layout and verification tool set among chip designers of medium-scale, mixed signal ASSPs and ASICs, has released version 16 of its HiPer Silicon fullflow design suite, offering designers a complete analogue and mixed-signal design flow from digital (HDL) and analogue (Spice, Verilog-A) electrical design and simulation, through synthesis to physical layout and verification. Among the changes that Tanner is offering with this release is the OpenAccess database, which the company regards as “a most significant development in the semiconductor design tools market”. The objective is to enable customers to use Tanner tools, or any other provider’s tool, at any point in the design flow – to step in and out of the the tool chain – with complete tool interoperability while maintaining data in the single database: and to bring a new degree of flexibility and accuracy to process design kits (PDKs) from a variety of silicon foundries. Interoperable PDKs should be usable, Tanner says, with any software flows and with the same common database. Acknowledging that foundries will verify their PDKs against the tool sets of the biggest companies in the sector, Tanner was faced with the task of having its tools interpret all aspects of the design data in the same way. Some of this was specified, the company says, and some had to found by trial-and-error, a lengthy process. Partly as a consequence of this progress towards an openaccess model, version 16 now permits a much higher degree of collaborative and distributed design activity, with team members able to work on the same database with greater ease. Tanner has also added a “traditional” logic design flow to its AMS (analogue/mixed-signal) offering, with HDL through synthesis to layout; synthesis has come from Incentia, and a digital simulator from Aldec has been added. Other enhancements in v16 include; new capabilities for back-end (layout); improved file loading and rendering speeds; improved physical verification (HiPer Verify); new capabilities for front-end (schematic capture, simulation, waveform viewing); integrated mixed-signal simulation (Verilog-AMS co-simulation); plus parametric plots, scatter plots and improved text control and graphics manipulation. - by Graham Prophet Tanner EDA, www.tannereda.com Open source RF hardware for wireless innovation By analogy with the innovation spurred by open-source exemplars such as Linux, and by hardware standards such as Arduino, Lime Microsystems aims to drive innovation in use of the RF spectrum by launching an open-source RF initiative: the non-profit organisation is initially based around a low cost, easy to use, fully configurable RF platform with pre-made boards and free, open, editable design files. Myriad-RF is a website, aspiring to become an on-line community, that aims to give both experienced design engineers and hobbyists a range of low-cost RF boards and free design files available for general use. Future board designs will come from the wider Myriad-RF community, with the first board (Myriad-RF 1) designed by Taiwanese distributor Azio Electronics. Lime markets highly integrated, single chip programmable transceivers, that you can set up to work in any one of a wide span of RF bands, with multiple modulation schemes, and with any suitable baseband signalling. In effect, its product is a software-defined-radio-on-a-chip. Its first product (LMS6002D) reached production in late 2010 and the company claims a 10 EDN Europe | MARCH 2013 www.edn-europe.com


EDNE MARCH 2013
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