New Industry Products

Microchip Technology Announces Digital Signal Controllers To Bring Digital Power to Mainstream Applications

March 29, 2009 by Jeff Shepard

Microchip Technology Inc. announced the first seven next-generation 16-bit dsPIC® Digital Signal Controllers (DSCs) for common, multi-loop Switch-Mode Power Supplies (SMPSs) and other power-conversion applications. These devices, offered in what is described as the industry’s smallest DSC packages for digital power conversion (with as small as a 6 x 6mm footprint), are provide up to twice the performance at a significantly lower price than Microchip’s first SMPS family.

The devices feature an "Intelligent Power Peripheral," which includes interconnected analog comparators, Pulse-Width Modulators (PWMs) and Analog-to-Digital Converters (ADCs) that are specialized for digital-power applications and can be software configured to adapt to a variety of topologies. This topology flexibility is said to give power-supply designers the complete freedom to optimize for specific product applications. And, with the dsPIC33’s in-circuit programming capabilities, common SMPS platforms can be differentiated late in the production process, saving both time and cost.

"Microchip breaks new ground with this family of digital-power DSCs," said Sumit Mitra, Vice President of Microchip’s High Performance Microcontroller Division. "Digital power is now offered at price, performance, flexibility and efficiency levels that are expected to ignite the emerging digital-power revolution."

Industry analysts concur that the market opportunity for digital power is expected to grow significantly over the next several years. According to Darnell Group President Jeff Shepard, "Digital-loop control is projected to grow at almost five times the unit growth rate of the overall power-supply market over the next five years. By 2013, the digital-loop-control market is projected to be 1.4 billion units."

The seven new dsPIC33F "GS" series digital-power DSCs enable digital control loops with four to eight high-speed, 1ns resolution PWMs, up to four 20ns comparators, each with an integrated Digital-to-Analog Converter (DAC) and one or two 10-bit, on-chip ADCs, providing 2 to 4 Million Samples Per Second (MSPS) for low latency and high-resolution control. These devices range from 18 to 44 pins and 6 to 16 KB Flash memory, and are pin compatible with Microchip’s initial digital-power DSC family. They feature interactive peripherals that both minimize the intervention of the processor and are able to handle the real-time needs of high-speed current-mode control.

These DSCs are well suited for ac-dc converters, dc-dc power-converters and other power-conversion applications, such as embedded power-supply controllers, power inverters, Uninterruptible Power Supplies (UPSs) and digital lighting. Additionally, their 1ns duty-cycle resolution PWMs can easily handle the precise timing requirements of all switching power-supply topologies, including the precise synchronous rectifier timing requirements.

The new digital-power dsPIC33Fs enable full control of the power-conversion process, via software running on the DSC and through its high-performance and highly configurable integrated peripherals. With these DSCs, digital power designers are not limited by analog-control design constraints. Components do not need to be "oversized" to account for component variation. Component drift and temperature compensation are no longer mainstream considerations, and manual tuning at the end of the manufacturing line can be eliminated. Fewer product platforms can serve a wider range of applications, since they are differentiated through software rather than hardware. Additionally, new fully digital topologies provide designers with a new degree of freedom to develop supplies with improved power density and improved cost effectiveness.

The dsPIC33F "GS" series devices offer 10 modes of PWM operation, including standard, complementary, push-pull, variable-phase and center-aligned. The on-chip, 10-bit ADCs have up to 12 input channels and sample at 2 MSPS, with a combined conversion rate of 4 MSPS for family members with two ADCs. Advanced sampling capabilities include individual triggers for each of the four sample and holds, which allow precise individual or simultaneous sampling modes. The on-chip analog comparators can be used as fault/current-limit inputs for fast shutdown of the PWMs, externally resetting the PWM periods; and also for triggering ADC conversions with no software overhead.

The dsPIC33FJ06GSXXX devices have 6 Kbytes of Flash and two PWM generators; the dsPIC33FJ16GS4XX have 16 Kbytes of Flash and three PWM generators; and the dsPIC33FJ16GS5XX have 16 Kbytes of Flash and four PWM generators. All devices in this family operate between 3.0 and 3.6V.

The dsPIC33FJ06GS101 is available in an 18-pin SOIC package. The dsPIC33FJ06GS102, dsPIC33FJ06GS202, dsPIC33FJ16GS402 and dsPIC33FJ16GS502 are available in 28-pin SOIC, SPDIP and 6 x 6mm QFN packages. The dsPIC33FJ16GS404 and dsPIC33FJ16GS504 are available in 44-pin TQFP and QFN packages. These DSCs start at $1.96 each in 5,000-unit quantities.