TI boosts Piccolo MCUs with control-loop-centric accelerators
TI positions this series of MCUs as providing (up to) a doubling of system performance without doubling cost or changing a hardware or software design. They use the established C2000 Piccolo architecture and maintain compatibility within that family, but add dedicated accelerator blocks, and uprate the core DSP engine from 90 MHz to 120 MHz. This, TI says, boosts execution speeds of control tasks in industrial applications such as telecom rectifiers, server power, solar micro inverters, frequency inverters and automotive HEV/EV. The F2807x MCUs also provide many analogue and control peripherals to enable more integrated control applications. They are scalable with the previously announced C2000 Delfino F2837xS and F2837xD MCU generations.
One of the added function blocks is the CLA, or real-time control accelerator. This unit relieves the main core of real-time-intensive and -critical functions, avoiding the need to rigorously partition cycles from the main core’s execution. It can double the throughput of the F2807x MCU, providing an additional 120 MHz of floating-point processing capability. This additional bandwidth allows designers to run parallel math-intensive or time-sensitive signal processing tasks. Offloading these tasks to the CLA enables the CPU to focus on general system tasks such as diagnostics, communications, and motion profiling. The CLA has its own dedicated instruction set, and is supported in the TI development environment with its own function libraries.
A further accelerator block, the trigonometric math unit (TMU) places in hardware many of the trigonometric or geometrical functions – for example, sin, cos, atan, divide, square root – needed for transforms and motion profiling; it typically cuts the clock cycles needed to carry out, for example, angle calculations, by 80-90%. Instructions that are best executed by the TMU are automatically trapped and directed by the code compiler.
next; analogue integration…
F2807x MCUs have high-end, smart analogue and control integration — including a flexible, enhanced pulse-width modulator (PWM) that supports all digital power topologies — to decrease digital control system complexity. Three 12-bit ADCs increase sampling throughput by allowing designers to do simultaneous tasks such as monitor voltages and currents of three-phase motors while simultaneously decoding high-frequency resolver feedback. The MCUs can simultaneously process eight delta-sigma modulated channels, each with threshold comparators and a seamless interface to the TI AMC1204 isolated delta-sigma modulator, for isolated current and voltage measurements. Window comparators provide critical power stage protection. New the the MCU family in this series are three 12-bit DACs; and an EMIF interface to allow memory extension.
Using the same C28x core and many of the same peripherals, the C2000 Piccolo F2807x MCUs are pin- and software-compatible with the previously introduced dual-core Delfino F2837xD and single-core Delfino F2837xS MCUs, enabling motor developers to get to market faster with a variety of products that feature a range of signal processing, flash performance, and analogue and control peripheral options. The C2000 F2807x Experimenter’s Kit and controlCARD allow designers ease in evaluating the C2000 Piccolo F2807x MCUs for their latest innovations.
Software development comes with examples, header files, and application libraries in the controlSUITE software. The Eclipse-based Code Composer Studio™ integrated development environment v6 accompanies these MCUs, and third-party support from Altair provides more software programming options for this new platform.
Production versions of the F28075 and F28074 (TMS320F28074) will start at less than $9 (1000). Evaluate the Piccolo F2807x MCUs using the Experimenter’s Kit docking station (TMDXDOCK28075) for $189 and the modular controlCARD (TMDXCNCD28075) for $129.