1. The dsPIC33F GS series digital-power DSCs enable digital control loops with four to eight high-speed, 1ns resolution PWMs.
2. Just-released trench heXFeT power MOSFeTs developed by International rectifier offer a package current rating of 195a.
While financial woes of the banking world continue to plague many international semiconductor businesses, the power electronics sector still keeps pumping out innovative new products and technology.
We all know that future consumer and commercial products designs have to be frugal and efficient when it comes to power consumption. This design challenge is heightened by the continuing development of more product capabilities and functions, which in and of themselves demand greater processing power.
The more we ask of processors, the hotter and more power-demanding they naturally become. Many of these market demands are satisfied by technological breakthroughs from the power semiconductor sector. Here, we’ll take a look at some of the latest.
Not wanting to do things in a small way, Microchip Technology Inc. developed seven next-generation 16-bit dsPIC digital signal controllers (DSCs). These chips are targeted at common, multidrop switch-mode power supplies (SMPSs) and other similar types of power-conversion applications.
They come in what Microchip claims is the industry’s smallest DSC packages for digital power conversion (with as small as a 6 x 6mm footprint). Overall, the devices provide up to twice the performance at a significantly lower price than the company’s first SMPS family.
ANALYSTS ATTITUDES
Industry analysts are saying that the market opportunity for digital power is expected to grow significantly over the next several years. Microchip claims that the seven new dsPIC33F “GS” series digitalpower 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 Msamples/s (MSPS) for low latency and high-resolution control.
The devices range from 18 to 44 pins and 6 to 18kB flash memory, and are pin-to-pin compatible with Microchip’s initial digital power DSC family (Fig. 1).
The design features an “Intelligent Power Peripheral,” which includes interconnected analog comparators, pulse-width modulators (PWMs), and analog-to-digital converters (ADCs) that are specialised for digital- power applications and can be software-configured to adapt to various topologies. Such topology flexibility gives power-supply designers the freedom to optimise for specific product applications. Also, thanks to the dsPIC33’s in-circuit programming capabilities, common SMPS platforms can be differentiated late in the production process, saving both time and cost.
The new devices are supported by a selection of development tools, including the new Buck/Boost Converter PICtail Plus Daughter Board. This comprises two independent dc-dc synchronous buck converters and one independent dc-dc boost converter. All of the necessary power, drive, and control signals are presented to board connectors. The board can control two buck stages, or one buck and one boost stage, via the demo software running on the board’s dsPIC33 DSC.
SET-TOP SAVINGS
Moving on to the set-top-box (STB) business, one of the biggest providers of semiconductor products to that market sector, STMicroelectronics, extended its commitment to saving energy on STB applications. ST says it supports the moves toward an assessment of STB performance through total energy consumption as used in other sectors of the consumer electronics industry.
Reducing the energy consumption of STBs benefits all parties within the supply chain: OEMs can differentiate their products by receiving energy-efficient markings, such as the Energy Star award, while consumers can potentially benefit from reduced electricity bills.
Today, STBs are sold predominantly on features and cost. In the future, STMicro believes that consumers will broader look at the total cost of ownership, which includes the initial purchase price as well as power-on costs and disposal of the equipment when it’s no longer required.
To that end, STMicro’s strategy focuses on reducing waste energy by including flexible power-management features that monitor and adjust the energy consumed by components within the STB environment. These components can be outside the STB, e.g., in the case of the low-noise block (LNB) within a satellite dish; large subsystems within the STB such as a hard disk; or even individual modules within the silicon devices themselves.
STMicro’s latest STB devices, including the high-definition single-chip STi7105, STi7111, and STi7141 decoders, are supplied with a software driver called STPOWER that controls all power aspects of the device. This application programming interface (API), which can be called from any application within the STB software stack, is common to all devices. It allows for flexible control at a component level to create application-specific active- and passive-standby modes. In this environment, the STB will feature very fast resume times from passive standby, thereby encouraging people to use this feature.
In addition to programmable power-management features, STMicro is also developing silicon technologies and design methodologies that reduce power consumption. The company is now manufacturing in a 55nm process technology, which is also optimised for lower power and this alone saves approximately 10% of power when compared to non-power-optimised 55nm technologies, says STMicro.
CLIMBING THE RATINGS
News-making packaging advances comes by way of International Rectifier. The company claims a 60% increase in package current rating with its new trench HEXFET Power MOSFETs is International Rectifier (Fig. 2).
The new devices provide a package current rating of up to 195A and deliver an improved on-state resistance (RDS(on)) compared to previous offerings. Moreover, the seven-pin D2PAK achieves a package current rating of 240A and offers a further reduction in RDS(on) over the D2PAK.
The higher current rating from these packages can provide more guard band from unwanted transients. Moreover, it helps reduce part count in parallel-type topologies where several MOSFETs share high current.
The N-channel MOSFETs have a voltage range of 60V to 200V and are qualified to industrial grade and moisture sensitivity level 1 (MSL1). The devices are lead-free and RoHS-compliant.
HIGH SURGE CAPACITY
NXP Semiconductors developed a range of transient voltage suppressor (TVS) diodes housed in its new FlatPower package, SOD123W. Offering a 400W peak pulse power rating (10/1000μs), the new diodes dissipate around 67W/mm2 surge per PCB area.
This, says NXP, is more than twice the surge capability of comparable TVS products in similar packages. Such high surge capabilities over smaller areas will enable engineers to save space on the PCB while delivering optimum power performance. In addition, engineers will be able to integrate more functions on the PCB.
The new TVS diodes are designed to protect voltage-sensitive components against transient voltage in various electronic applications like power supplies, data or signal lines, medical equipment, and telecommunications circuits. Qualified to the AEC-Q101 standard, the new FlatPower TVS devices can be used for all automotive and industrial applications.
Because of its very low leakage current of 1nA and small size, the SOD123W TVS device can also be used in battery-driven products like mobile phones and notebooks, where space is a constraint. With a significantly lower height of 1mm and compact size (2.6 x 1.7 x 1mm), the SOD123W occupies only half the PCB area when compared to competitive TVS diodes in SMA packages. The new FlatPower SOD123W package fits on a SMA footprint, providing a solution for a 1:1 replacement.
....AND FINALLY
The Endicott Research Group (ERG), has created a European office in Switzerland, naming Roland Knuchel as European Sales Manager. ERG, based in Endicott, N.Y., USA, is a manufacturer of dc-ac inverters and LED drivers for powering LCD backlights.
A resident of Switzerland, Roland Knuchel worked with ERG as President/CEO of Milgray Distribution in Switzerland from 1986 to the present.