The demand by portable and laptop computers for smaller switching power supplies is forcing power supply vendors to look at costly control circuits and ceramic adaptors: Electronic News says that cost is not the only issue since size reductions have been less marked than expected because power sources that approach the 1MHz mark require extra electromagnetic interference filtering and heat sinking hardware; consequently, most switchers are still operating under 300KHz, although OEM pressure is mounting and supply vendors are looking to introduce new products in the 500KHz to 1MHz range; going to higher frequencies is the primary way to reduce switcher size and although cost is still a major stumbling block, component pricing is likely to fall demand rises and switcher production increases.
