Precision movement and positioning systems used in industries such as automated manufacturing and pharmaceutical production can be quieter, smaller, lighter, simpler and more efficient using the single-chip digital stepper motor controllers announced today by STMicroelectronics. The two cSPIN ICs being released are the L6480, which supports micro-stepping operation at up to 1/128 steps resolution, and the L6482 featuring the predictive control algorithm and the auto-adaptive decay mode.
Applications are expected to include: robotic systems and industrial automation, stage lighting, security cameras, camera focusing mechanisms, sewing machines, and general positioning and rotation equipment. In each case the small size and low weight of the cSPIN solution enables lower-cost and more responsive equipment compared to using a conventional multi-chip drive. This helps improve overall system efficiency by eliminating the need for shunt resistors, thereby reducing unwanted power dissipation.
cSPIN also allows precise control over rotation speed, which is particularly important for repeatable, accurate mixing of liquids in applications such as handling of medical samples. For all applications, the smooth and noiseless operation delivers advantages for users, especially in quiet environments such as laboratories or on hospital premises.
As the world’s first devices of their type, cSPIN micro-stepping controllers for 2-phase stepper motors provide several technical advantages over existing alternatives. Communication with the main system uses high-level commands via a standard Serial Peripheral Interface (SPI). The on-chip gate-driver circuitry, for the motor’s power stage, can operate from 8 V to 85 V, which allows applications to scale smoothly over a wide power range up to 300 W. ST’s digital motion engine is optimized to overcome known challenges such as avoiding resonance to ensure exceptionally smooth and quiet motor operation.
ST’s cSPIN family requires no motor-control software and simplifies system design by performing all calculation, control and interfacing functions in a single chip. Competing solutions require software and multiple discrete chips, which designers must combine before starting to develop their applications. With cSPIN, projects can begin using an ST evaluation board containing the control IC, which can be connected immediately to a stepper motor enabling rapid prototyping.
Major features of cSPIN controllers include: Digital motion engine, gate driver and SPI interface on one chip. Programmable speed control and positioning. Integrated protection mechanisms: over-temperature, low bus voltage, over-current, motor-stall. 5 Mbit/s SPI interface. Fully programmable gate driving. Innovative voltage mode control with internal BEMF compensation (L6480). Advanced predictive current control with auto-adaptive decay mode (L6482). And low standby current.
The devices are now ready to enter volume production priced at $3.00 in quantities of 1,000 units.