 | 'C24x DSP controller |
To meet the need for more advanced digital motor-control solutions, TI has announced the TMS320C24x DSP controller, the first DSP optimized for motor-control systems. The new device supports motor commutation, command generation, control algorithm processing, data communications, and system monitoring functions.
Leveraging TI's DSP core technology, the 'C24x integrates a 20-MIPS TMS320C2xx 16-bit, fixed-point core to provide enough processing for the modern control algorithms that support a motor-industry trend toward the use of brushless motors in a broad range of control applications. The 'C240 also integrates a unique motor-control event manager whose features allow the device to generate outputs which can robustly drive all motor types.
The 'C240 highlights TI's expertise at producing application-targeted DSP solutions by integrating a DSP core with digital and mixed-signal peripherals on a single chip. The device includes the DSP core, the event manager, two serial interfaces, a pair of 10-bit A/D converters, 32 bits of digital I/O, a watchdog timer, and 16K words of ROM. Also announced is the TMS320F240, which replaces the ROM with 16K words of flash EPROM memory.
"Because this device integrates a DSP core with a comprehensive set of motor-control peripherals, the 'C240 represents a major breakthrough toward enabling low-cost, closed-loop motor-control designs," said Gregg Bennett, TI DSP digital motor control marketing manager.
The 'C240's integrated event manager is key to providing designers with a complete motor-control solution. It features three up/down timers and nine comparators which, when coupled with flexible waveform generation logic, can create up to 12 pulse-width-modulation (PWM) outputs. Also included is dead-band generation logic and a state-space vector PWM generator for optimized transistor switching, and four capture inputs, two of which can serve as direct inputs for optical-encoder quadrature pulses. All these features help the 'C240 reduce power consumption, vibration, and system component count.
In automotive applications, the 'C240's control capabilities can help automotive engineers improve system performance and decrease cost through the elimination of hydraulic subsystems for steering and braking.
In these systems, inexpensive brushless motors can now be connected directly to mechanical actuators, therefore allowing removal of the hydraulics. These direct-drive electronic systems are more reliable and cleaner and also remove the engine load incurred when driving hydraulic pumps. Also, electronic controls weigh far less, are easier to install, and occupy less physical space.
Electronic brake controllers can use the 'C240 to directly drive high-torque motors, allowing a localized, intelligent control loop for advanced anti-lock brake systems. In electrical power steering designs, the 'C240 can be programmed to exhibit a variable steering profile, with relatively light steering response at very low speeds, and tight, sporting response at highway speeds.
The 'C240 allows controllers for industrial applications to be made smaller, cheaper, quieter, and more energy efficient through the elimination of mechanical coupling equipment. For example, motors can now be connected directly to paper production, textile manufacturing, and food-processing systems that have traditionally used hydraulics or single-speed motors coupled to belts and pulleys to collectively vary controller speeds.
Today, washing machines, heating/ventilation/air-conditioning (HVAC) systems, and other major appliances typically use mechanical linkages to achieve variable speed and direction. Once again, the 'C240 will help eliminate these noisy maintenance-prone parts through variable-speed, direct-drive electric motor control.
'C240 programmability lets designers produce smarter appliances. In a horizontal-axis washing machine, a wash cycle can use electronically-programmed speed changes to optimize wash and spin cycles to get clothes cleaner using less detergent and water. Also, when starting a cycle, DSP algorithms allow for gradual acceleration after each motor direction reversal, reducing noise and wear on parts.
The 'C240 is code compatible with TI's 'C1x, 'C2x, 'C2xx, and upward code compatible to the 'C5x DSP device generations. The device leverages TMS320 fixed-point DSP software development tools and JTAG emulation support for ease of development. Third-party products featuring 'C24x support are also planned.
US suggested resale pricing for the TMS320C240 is planned for less than $10 in high-volume production (100,000 units), while the 'F240 with on-chip flash will be 30-50% higher. The 'F240 will sample in the first quarter of 1997, with volume production in late 1997. Production of the 'C240 is planned for 1Q98.