Power Integrations' New LinkSwitch®-II Exceeds Global Energy-Efficiency Standards; Eliminates All Secondary Feedback Circuitry in Switching Converters With Accurate CV/CC Output : Accurate Integrated Offline Switcher IC Reduces Power Supply Component Count by 30%

Share Article

Power Integrations (NASDAQ:POWI), the leader in high-voltage analog integrated circuits for energy efficient power conversion, today announced the introduction of its LinkSwitch-II family of highly integrated AC-DC switched-mode power conversion ICs with very accurate primary-side control. LinkSwitch-II dramatically simplifies constant-voltage, constant-current (CV/CC) converters, and enables consumer products to meet all worldwide energy-efficiency and no-load regulations, such as ENERGY STAR 2.0 for external power supplies. The new ICs are ideal for applications such as chargers for cell phones and cordless phones, high brightness LED drivers and other accurate CV or CC applications.

News Image

LinkSwitch-II, a new generation in Power Integrations' extremely successful LinkSwitch series of ICs, simplifies the design of accurate output CV/CC converters by eliminating the need for optocouplers and all secondary-side CV/CC control circuitry as well as all control-loop compensation circuitry. By integrating all control and protection circuitry plus a 700 V MOSFET in an 8-pin package, LinkSwitch-II significantly reduces component count, space and system cost while increasing reliability. Output CV/CC tolerances of +/-5% and +/-10% respectively are achieved over a 0 – 100 °C temperature range by incorporating precision-enhancing features that compensate for transformer inductance tolerances, input line variations, output cable voltage drop (LNK61x only) and external component temperature variations. LinkSwitch-II also offers frequency jittering to greatly reduce EMI filter costs. Sophisticated protection and safety features include auto-restart output short circuit protection and hysteretic thermal shutdown. IEC 60950-1 HV creepage requirements between Drain and all other pins are met and all single point failures are handled safely.

In an example cellphone charger design of 5V/1A, 5 W, LinkSwitch-II offers a simple path to ENERGY STAR EPS 2.0 compliance by achieving average efficiency levels of up to 75% at 25%, 50%, 75% and 100% loads across a 115 to 230 VAC input range. The On/Off control scheme employed in LinkSwitch-II, coupled with low IC power consumption and elimination of secondary-side current sense resistor and control circuitry, provides practically constant efficiency across the entire load range and a no-load consumption of under 30 mW.

Comments Doug Bailey, vice president of marketing at Power Integrations: "LinkSwitch-II sets a new standard in the level of integration achievable in a switching power supply design. It uses primary side regulation to accurately control the output current and voltage, eliminating an expensive opto-coupler and all of the secondary feedback and compensation components. A charger designed with LinkSwitch-II has 9 fewer components compared to the previous generation of LinkSwitch and up to 15 fewer components when compared to discrete designs. LinkSwitch-II offers accurate cable drop compensation which significantly reduces the cost of the output cable by minimizing its copper content, without sacrificing output performance. It also requires a smaller transformer using less copper and core material."

Bailey continues: "Lack of secondary feedback sensing components increases the efficiency of LinkSwitch-II-powered chargers to levels approaching 80%. Furthermore, LinkSwitch-II dramatically reduces no-load consumption, the power consumed from the wall when disconnected from the appliance, to levels that are difficult to measure, saving consumers money on their electricity bills. Overall, the LinkSwitch-II solution greatly simplifies the design, is less expensive to build, and is easier on the planet's physical resources and energy supply."

Further underlining LinkSwitch-II's green credentials, all family members are produced in halogen-free, RoHS-compliant packaging, which is increasingly being demanded by end customers such as Apple, Nokia Samsung and LG.

Power Integrations' Green Room web site (http://www.powerint.com/greenroom) contains information on the issue of energy waste from inefficient power supplies, as well as tips on how to design products that minimize the amount of energy wasted by household and office electronics. The Green Room also provides a comprehensive guide to energy-efficiency standards around the world, as well as a host of reference designs and software to assist in the design of energy-efficient power supplies.

About Power Integrations

Power Integrations is the leading supplier of high-voltage analog integrated circuits used in energy efficient power conversion. The company's breakthrough integrated-circuit technology enables compact, energy-efficient power supplies in a wide range of electronic products, in AC-DC, DC-DC and LED lighting applications. The company's EcoSmart® energy-efficiency technology, which dramatically reduces energy waste, has saved consumers and businesses around the world more than an estimated $2.8 billion on their electricity bills since its introduction in 1998. Reflecting the environmental benefits of EcoSmart technology, the company's stock is included in clean-tech stock indices sponsored by Nasdaq (Nasdaq:CLEN) (Nasdaq:CELS) and the American Stock Exchange (AMEX:CTIUS). For more information, visit the company's website at http://www.powerint.com.

Share article on social media or email:

View article via:

Pdf Print

Contact Author

Peter Rogerson
Visit website