ADI adds mixed-signal control processor for industrial motor and solar inverter designs

September 26, 2013 // By Graham Prophet
Analog Devices' ADSP-CM40x integrates a high-precision A/D converter and the fastest ARM Cortex-M4 to meet the performance demands of next-generation industrial control and electrical grid equipment

The mixed-signal control processor integrates an embedded dual 16-bit A/D converter with up to 14 bits of accuracy together with a 240-MHz floating-point ARM Cortex-M4 processor core. Analog anticipates applications for highly accurate, closed-loop control in servo, motor-drive, solar photo-voltaic (PV) inverter and other embedded industrial functions.

The ADSP-CM40x series is the first of a new generation of mixed-signal control processors being developed by Analog Devices for precision control applications. In addition to its analogue conversion performance and 380-nsec conversion speeds, the ADSP-CM40x provides a number of other features such as a full sinc filter implementation to interface directly to isolated sigma-delta modulators (AD7400A/AD7401A) which are used in shunt-based current sensing system architectures. The availability of an on-chip sinc filter eliminates the cost and engineering resources required to implement that function in an FPGA.

ADI has provided integration with the MathWorks tool set. Through the use of MathWorks’ ARM Cortex-M optimised Embedded Coder and tool suites, Analog Devices enables bringing designs from simulation to productised code implementation in an embedded platform. “Through optimised code generation, device drivers and compiler suites, Analog Devices’ new ADSP-CM40x series enable engineers to plug their designs directly into an environment for model-based design using MATLAB and Simulink software, streamlining the workflow from system modelling to controller deployment to verification and certification,” said Tom Erkkinen, products manager, MathWorks. “This structure defines a complete model-based development platform, allowing engineers to focus on faster development of more efficient systems.”

Solar PV has become the largest source of new generation capacity added to the global electricity grid - with a cumulative installation base of 100 GW - and is set to become the fastest growing source of renewable energy generation over the next decade. Increased measurement accuracy, supported by the ADSP-CM40x’s integrated high precision converters, is driven by ever more stringent grid compliance requirements. This coupled with faster power control loops, fuelled by the emergence of GaN (gallium nitride)