Perhaps the greatest asset of Freescale Semiconductor's new motor control offerings are their flexibility of use. On-chip flash program and data memories permit shorter development cycles and allows manufacturers to stock and use a single controller for multiple designs. Subsequently, flash also permits the manufacturer to install the latest control programs at the end of the production line or update control programs in the field, if necessary. This improves the service life of the motor being controlled, decreases time-to-market and provides even further cost savings. Commonality Between Peers Choice is not a Zero-Net-Gain. Both types of controller provide wide latitude in applications, thus covering the entire spectrum of opportunity.
Perhaps the greatest asset of Freescale Semiconductor's new motor control offerings are their flexibility of use. On-chip flash program and data memories permit shorter development cycles and allows manufacturers to stock and use a single controller for multiple designs. Subsequently, flash also permits the manufacturer to install the latest control programs at the end of the production line or update control programs in the field, if necessary. This improves the service life of the motor being controlled, decreases time-to-market and provides even further cost savings.  Commonality Between Peers  Choice is not a Zero-Net-Gain. Both types of controller provide wide latitude in applications, thus covering the entire spectrum of opportunity. Freescale Semiconductor's legendary microcontrollers for motor control are now teamed with the leading contender for DSPcontroller in this same market. This establishes Freescale Semiconductor's breadth of market coverage and product offerings. There are truly no competitive alternatives.  Control Safety  In addition to being fast, powerful and low-cost, any device used in real-time control of motors must be capable of dealing with the important safety issues: personal safety, as well as inherent protection mechanisms for the equipment in which it's installed. With this in mind, Freescale Semiconductor's motor control families offer both hardware and software programmable features that not only protect the motor and control electronics, but also the equipment in which it is installed and the people who work around the machines. Overload conditions that could present a safety hazard due to overheating can be avoided with the speed of digital control. Fault inputs that provide an emergency mechanism to immediately disable the pulse width modulation (PWM) outputs, preventing driver and/or motor damage or failure. Crystal oscillator failure and locked rotor detection are also provided to detect associated system failures and provide programmed shutdown. Write once control of certain programmable features (i.e., PWM polarity, etc.) prevents “run away” program conditions or unintended operations from altering the value programmed in the control register, saving the system from possible catastrophic failure. Once this condition or operation occurs, this value cannot be changed until power to the device has been removed and then reapplied. Current and temperature sensors embedded within the driver/motor stage and connected to ADC channels can be used to provide proper system shutdown if an out-of-range condition occurs. For example, a submersion pump in a fuel tank could overheat if the rotor slowed down too much causing a dangerous condition. By detecting the decreased rotational speed or high current and/or over-temperature condition, the controller could safely shutdown the pump before the overheating caused a dangerous condition and could also notify the proper authority that the condition occurred.  Choice of Champions  Now for the really hard part, selecting between these excellent products for your implementation. While both part families offer many of the same features, the ultimate choice is the designer. Any motor control algorithm can be executed by any motor controller given the proper hardware. The only real difference is the speed of execution that can be attained by the processor and the details of algorithm control required. For open-loop (no feedback) or electromechanical closed-loop feedback (supplied by a shaft encoder) systems used for applications controlling motor speed or position, the microcontroller may offer the best cost/performance choice. However, if the motor being controlled is fast, has many windings, is being used in a continuous torque application or requires an additional microcontroller or microprocessor to control system operation, then the DSPcontroller may offer the best alternative. Likewise, when very high speed motors are employed or the motor must be tightly controlled with a closed-loop algorithm (like high-speed reluctance or low-speed traction motors), the optimum choice will be most likely be a DSPcontroller. With either choice, the designer, manufacturer and customer wins.  Tools to the Kingdom  To ease the pain of new system development and to permit rapid prototyping for shortened time to market, Freescale Semiconductor has available a sophisticated set of software and hardware development tools. Based on an easy-to-use integrated development environment (IDE) platform, development tools for either controller system look and feel much the same, allowing the development engineer to concentrate on the design.  Hardware Support Separate evaluation modules (EVM) for each controller are capable of being interchanged with an available, low-cost, common hardware development platform consisting of power supply, motor driver circuit and 100 watt motor/brake assembly. This combination permits both microcontroller and DSPcontroller to be thoroughly evaluated in operation for any application. Connection to the each EVM is provided by a simple parallel connection through the printer port of most personal computers. This means offers easy program download from the host computer to the EVM. An on-chip debugger can then be used to assist in developing program control code. The low-cost EVMs are also available as a stand-alone module for software only evaluation or with an available sub-fractional horsepower motor for even lower cost evaluation of a motor control design. In-Circuit Emulation is provided through use of the JTAG/OnCE port located on the DSPcontroller EVMs. This port permits almost real-time, direct access to important processor machine states, registers and memory locations to significantly decrease the time for development. Software Support Freescale Semiconductor, through its MetroWerks operation, offers powerful C compiler, assembler, and linkage loader tools for the DSPcontroller that promote structured software development. The entire software development platform is tied together under a powerful integrated development environment (IDE). Available software also includes a simulator and a debugger, also operating under within the IDE.
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