According to STMicroelectronics, the company’s Structured Architecture of Bridges and Regulators (SABRe) IC is the first customizable mixed-signal chip for motion and power management for printers and similar equipment. The device is intended to reduce both the cost and development time of such projects.
“ST’s SABRe represents a first-of-its-kind solution with a complete set of analog functions for motion and power-management applications,” said Vittorio Peduto, General Manager of ST’s Computer Systems Division. “Customers get a highly configurable and customizable device that offers the flexibility of a dedicated product at a fraction of the time and cost required by a full-custom design approach.”
The SABRe includes a complete set of configurable and customizable analog functions for use in the motion and power-supply portions of printer applications. The IC can drive the motors that move the paper, the carriage, the service station and other parts of the printer. It can also generate the voltages needed for operating the pens, in addition to the other supplies on the pc board. Functioning as the master, the IC manages the entire power section of the application with specific programmable power-up routines before other digital ICs switch on.
Specifically designed to provide analog functionality, the SABRe IC compliments the company’s SPEAr (Structured Processor Enhanced Architecture) family of customizable digital engines. Together, these two parts are intended to provide a complete configurable platform for printer applications.
The capabilities of the SABRe can also directly challenge digital power control platforms in motor applications. According to Giona Fucili, CS Design Manager at STMicroelectronics, the SABRe controls the current in the motor when in stepper mode. Moreover, with a proper customization and depending on the application of the IC, several thousand gates are available, operating up to 30 MHz. They can be used to implement digital control loops for speed or positioning, reading the suitable data from external encoders or other sensors. This can be accomplished using the ADC embedded within the IC.
The main components of the SABRe IC (shown in the figure) include four configurable bridges that can also function as switching regulators. Bridges 1 and 2 have a diagonal RDS(ON) of 1.1 Ω and a maximum operating current of 2.5 A. Bridges 3 and 4 have a diagonal RDS(ON) of 1.6 Ω and a maximum operating current of 1.5 A.
The other components are a variable-voltage buck switching regulator; a switching regulator controller; a linear regulator; a multi-channel configurable 9-bit ADC; two operational amplifiers; a bi-directional serial interface and several general-purpose I/Os (GPIOs).
Certain architectural changes can be programmed via the serial interface or GPIOs. Fucili states this part can be reconfigured on the fly through these ports. Alternatively, the IC can be protected against unwanted on-the-fly reconfigurability.
More complex functions are implemented through customized metal layers that enable specific macro functions. The metal customization does not modify any active part of the silicon, minimizing the risk of undesired parasitic effects, which are a potential concern in mixed-signal ICs.
Among the possible configurations of the device, certain bridges can be interconnected to provide expanded functionality. For example, Bridge 1 and Bridge 2 can each be configured to perform the following functions: dc motor driver, two half-bridges, one super half-bridge, two switches, or one super switch. Bridge 1 and Bridge 2 can also be paralleled to form a super bridge.
Other high-power, high-voltage analog applications the SABRe addresses include industrial motor control. Moreover, the SABRe features low power consumption and minimal power dissipation in power-off mode, meeting the requirements of energy-efficiency programs, such as Energy Star.
Samples are available now, with volume production planned for Q4 2007. Pricing will be between $2.20 and $2.50 in OEM quantities.