Off-line switching power supply IC with integrated 900 V primary MOSFETs

     Power Integrations has released a new off-line switching power supply IC with integrated 900V primary MOSFETs. It includes ics suitable for high efficiency isolated flyback power supplies and ics suitable for simple non-isolated buck converters. Its applications include 480 VAC three-phase industrial power supplies as well as high-quality power supply designs for consumer electronics in areas with unstable power grids, tropical areas that are subject to frequent lightning strikes, or areas where high energy oscillations and surges frequently occur.

     New products include the 900V LinkSwitch™-TN2 IC for simple non-isolated buck converters and the three InnoSwitch™3-EP flagship series ics for 35 W extremely efficient isolated flyback power supplies. All 900 V series devices feature an internal control engine that delivers consistent high efficiency across the load range, making it easy for designs to meet energy-related product (ErP) limits. In addition, these devices provide multiple input voltage and load protections to further enhance system stability and reliability.

     The 900V LinkSwitch-TN2 IC provides a step-down converter switching power solution with the lowest number of components. The current-limiting points of these devices can be set externally, and automatic restart protection in short-circuit and open-loop failure conditions is fully integrated. The use of frequency modulation can significantly reduce EMI. Whether on the PCB board or in the IC package, the device ensures that the high-voltage creepage spacing and spatial distance between the drain pin and other pins meet the requirements.

     The 900V InnoSwitch3-EP flyback switching power Supply IC provides lossless input overvoltage protection detection and automatically interrupts the switch when the input voltage exceeds a selected threshold, preventing power damage in cases of severe input overvoltage. The device delivers industry-leading high performance (up to 90% efficiency) across all input voltages and load conditions, resulting in reduced power losses and a compact 35 W power supply design that does not require heat sinks. These 900V InnoSwitch3-EP ics feature Power Integrations' innovative isolated digital communication technology, FluxLink™, in addition to synchronous rectifier (SR), quasi-resonant (QR) switches, and precise secondary side feedback detection and control circuits. These characteristics enable high efficiency, high precision and high reliability of the power supply circuit, without the need for unreliable optocouplers.

     Silvestro Fimiani, Senior Product Marketing Manager, said: "These switching power ics enable designers of three-phase meters, motors, industrial auxiliary power supplies, home appliances and mobile phone chargers to achieve truly compatible power designs that meet the reliability expectations of users around the world. For example, Oems working to open up India's emerging market for high-quality consumer products are constantly experiencing problems with electrical damage and having to repair or replace returned products. Our 900V switching power supply ics provide low-cost and effective protection while significantly reducing operational and product support costs."