Pulse Announces New Flat-Coil Power Inductors
Pulse announced a new series of flat-coil surface mount (SMT) power inductors that lowers the inductor operating temperature of a notebook computer by as much as 5°C and improves battery operating time by 6%, increasing its efficiency and reliability. In addition, a special process is used to wind the flat wire in the inductor, resulting in an average 30% lower direct current resistance (DCR). These inductors are suitable for use in voltage regulator modules (VRMs) in notebook computers, desktop computers, workstations, and servers as well as in dc-dc point-of-load (POL) converters and other high-density, high-power, high-ambient-temperature applications.
Pulse’s patent pending PG0437NL series consists of four parts, the PG0437.321NL, PG0437.401NL, PG0437.451NL, and PG0437.601NL, with inductance values from 0.32 to 0.6µH with a peak saturation of 39A. These inductors use a power ferrite core material which results in 10 times lower core losses than iron powder or iron alloy cores while maintaining the same saturation current as 4040 iron powder inductors. A lower core loss significantly reduces the inductor temperature, increases efficiency and, as a final result, extends battery operating time. Evaluation of a notebook computer’s performance, using BAPCO MobileMark 2005 software, shows an average lower operating temperature of 5°C and 6% more battery operating time when using the PG0437NL inductor instead of an iron powder inductor. In addition, ferrite cores, unlike iron powder material cores, are not subject to thermal aging. Thus, they decrease any risk of thermal runaway when operating at high ambient temperatures and high output current loads.
A special process of winding the rectangular wires results in a DCR of 0.85mΩ, which on average is 30% lower than what existing inductors are currently offering. A decrease in DCR reduces copper loss (I2R) and helps to increase overall system efficiency. The series also offers a tight DCR tolerance of ±10%, suitable for current sensing applications. The series has a high peak saturation current from 21A to 39A and a maximum operating current rating of 33A. This current rating enables the inductors to handle the high-current requirements of microprocessors with a significant saturation margin.
Pulse’s PG0437NL series come in an industry-standard 4040 footprint of 12.5 millimeters (mm) x 11mm max with a low profile of 4.5mm maximum height, important for allowing even airflow over the entire circuit board to reduce hot spots. The inductors have an operating temperature of minus -40 to +130 °C. They are RoHS compliant and meet standard EIA481 requirements. Pulse’s PG0437NL Series is available in tape-and-reel packaging.
