Power Integrations launches LinkSwitch-HP for primary-side regulation to 90 W


Reduces component count, space, and cost while enhancing reliability compared to optoisolated designs

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Energy efficient, high-power off-line switcher with accurate primary-side regulation operates without expensive optoisolators for power supply applications between 9 and 90 W.

Power Integrations, has launched LinkSwitch-HP, a new family of energy-efficient, off-line switcher ICs that can deliver up to 90 W with accurate primary-side regulation. LinkSwitch-HP ICs use innovative control algorithms and the properties of the main power transformer and output diode — instead of optocouplers and related feedback circuitry — to determine the amount of power to deliver from the primary to the isolated secondary side. This method dramatically reduces component count, saving space and cost while enhancing reliability. Primary-side regulation is now standard in many low-power applications such as mobile-phone chargers, but until now has lacked the constant-voltage accuracy required in higher-power products. LinkSwitch-HP devices feature a multi-mode control architecture that radically advances the state of the art for this topology, making it a viable approach for power-supply applications from 9 to 90 W. Doug Bailey, VP of marketing at Power Integrations commented, "LinkSwitch-HP devices extend the power range of primary-side regulation up to 90 W, enabling designers to bring [its] benefits to such applications as tablet chargers, ultra-book adapters, LCD monitors and TVs, STBs, appliances, and embedded power supplies." LinkSwitch-HP devices automatically select their control mode according to prevailing line and load conditions to optimize conversion efficiency and response to transient load demands, while minimizing output ripple and audible noise. CCM (continuous-conduction-mode) operation results in reduced RMS currents, leading to higher efficiency and less heat dissipation, while 132-kHz, full-load operating frequency enables the use of smaller magnetics and LC post-filter components. LinkSwitch-HP ICs are capable of no-load power consumption of less than 30 mW at 230 VAC and are more than 50% efficient at 0.1 W input power, easily meeting all global energy efficiency regulations such as ErP (EuP), ENERGY STAR EPS V2.0, and EC Ecodesign Directive Tier 2 for external power supplies. The regulators also greatly reduce the cost and complexity of meeting the Chinese safety standard GB 4943.1-2011, which mandates the use of warning labels on power supplies that do not meet strict creepage and clearance rules. Similar to UL 60950-2007 and set to become mandatory on December 1st, 2012, the new rule requires designers to increase the primary-to-secondary clearance by a factor of 1.48 for power supplies used in equipment above altitudes of 2 km, or else add a warning label to the product. Warning labels are disliked by vendors as these decrease consumer confidence in product safety. LinkSwitch-HP ICs feature a comprehensive protection suite, including selectable current limit, programmable shutdown delay-time extension, brown-out, brown-in, over-voltage, over-current, and over-temperature protections. Engineering samples are available now, with production quantities expected by the end of August 2012. LinkSwitch-HP devices are available in two different package options: eSIP-7C and eDIP-12B, starting at $0.42 (10,000) for model LNK6763V. Two supporting evaluation demo boards are available upon request: RDK-321, a 17 W dual-output flyback converter for LCD monitors and RDK-313, a 30 W, 12 V single-output general-purpose adapter. Power Integrations