Power Integrations Expands TOPSwitch

Tag : power Supplies
Power Integrations, the leader in high-voltageintegrated circuits for energy-efficient power conversion, todayannounced a new, ultra-low-profile package for its popularTOPSwitch-HX family of AC-DC power conversion ICs. This small newpackage combined with the best-in-class efficiency and highoperating frequency of TOPSwitch-HX enables remarkably slim,compact, and lightweight power supplies from 20 to 100 watts.Applications include adapters for notebook computers, as well aspower supplies for LCD monitors and flat-panel TVs, in which slimform factor and high efficiency have become critical designcriteria.

The new "L" shaped lead-bend allows the company's innovative eSIPpackage to lie flat against the printed circuit board with theheatsink pad facing upwards. The device stands just 2 millimetersabove the board giving plenty of space for a heatsink and enablingextremely slender power supply designs.

The elegance of adapter designs enabled by the new package isdemonstrated by a new reference design (DER-196) for a 65 Wnotebook adapter only slightly larger than a standard deck ofplaying cards. The design, which complies with the upcoming ENERGYSTAR(R) 2.0 specifications for external power supplies, utilizes aTOP261 chip in the new eSIP-L package. The highly efficient ICcombines a 700 V switching power MOSFET with controller andsupervisory functions into a single monolithic IC, reducing theneed for bulky heatsinks required in designs using traditionalTO-220 packaged MOSFETs and discrete controllers, and eliminatingthe need to encase the electronics with thermally-conductivepotting compound. The package's 90-degree pin deflection enablesthe PCB, chip and heatsink to lie parallel to each other, while thehigh switching frequency of TOPSwitch-HX eliminates the need for anexpensive planar type transformer. This, together with PowerIntegrations' proprietary transformer design, greatly reduces boththe cost and size of the notebook adapter.

Comments Andrew Smith, product manager at Power Integrations:"TOPSwitch-HX has the best overall efficiency and lowest heatdissipation of any integrated flyback solution, which minimizes thesurface area and heatsink hardware required to radiate the heataway from the electronics. The eSIP-L package delivers the samethermal performance as the older TO-220 package but with a muchlower profile. Until now, slim power adapters have tended to besold after-market and use exotic technologies and even pottingcompound to achieve acceptable thermal performance - they'reexpensive. The combination of TOPSwitch-HX with the new low-profilelead-bend package makes it possible to build slimline adapters -just 15mm thick - using standard wire-wound transformers and simplemanufacturing techniques at a cost similar to a standard laptopadapter brick."

TOP260LN, TOP261LN and TOP262LN devices suitable for slim adaptersfrom 20 W to 100 W power levels are available in the new eSIP-Lpackage style immediately from $1.00/ea in 10K unit quantities.