New Industry Products

Power Integrations New LinkSwitch-HP ICs Introduce Primary-Side Regulation to Power Supplies Up to 90 Watts

July 24, 2012 by Jeff Shepard

Power Integrations announced LinkSwitch™-HP, a new family of energy-efficient, off-line switcher ICs that can deliver up to 90W output power with accurate primary-side regulation (PSR).

LinkSwitch-HP ICs utilize 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. Popularized more than a decade ago with the advent of Power Integrations’ LinkSwitch line, PSR 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 unique multi-mode control architecture that radically advances the state of the art for PSR, making it a viable approach for power-supply applications from 9 to 90W.

Comments Doug Bailey, vice president of marketing at Power Integrations, "Power Integrations was first to introduce integrated primary-side off-line switcher devices, and LinkSwitch products currently out-sell any competing PSR technology across a broad swathe of low-power applications from mobile-device chargers to LED lighting to appliance bias supplies and even smart meters. LinkSwitch-HP devices extend the power range of PSR up to 90 W, enabling designers to bring the benefits of PSR to such applications as tablet chargers, ultra-book adapters, LCD monitors and TVs, STBs, appliances and embedded power supplies. LinkSwitch-HP ICs deliver power and performance unequalled by any other PSR solution."

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. Continuous-conduction-mode (CCM) 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 30mW at 230Vac and are more than 50 percent efficient at 0.1W 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.

LinkSwitch-HP devices also reduce the cost and complexity of meeting 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 2000m, or else add a warning label to the product.

LinkSwitch-HP ICs feature a comprehensive protection suite, including selectable current limit, programmable shutdown delay-time extension, brown-out, brown-in, overvoltage, 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 offered in two different package options: eSIP-7C and eDIP-12B, starting at $0.42 each for 10,000-piece quantities (LNK6763V). Two supporting evaluation demo boards are available upon request: RDK-321, a 17W dual-output flyback converter for LCD monitors and RDK-313, a 30W, 12V single-output general-purpose adapter.

More news and information regarding the latest developments in Smart Grid electronics can be found at Darnell’s SmartGridElectronics.Net.