The November 5 issue ofPETech Times presented numerous key power ICs and passive components explored on the first day of the exhibition at the recent Power Electronics Technology Conference & Exhibition in Long Beach, Calif. This issue will examine developments encountered during the next two days at the show.
On the semiconductor front, suppliers such as Cree Inc., Infineon, Philips, Vishay Siliconix, Toshiba, STMicroelectronics and ABB Semiconductor unwrapped the latest in discretes and ICs. The passive sector witnessed further developments in planar magnetics from players such as Payton Planar Magnetics and TT electronics MMG. Capacitor maker Kemet boasted new developments in low ESR, surge robust tantalum and high-voltage ceramic chip capacitors. BI Technologies unveiled a new motor drive power module with control circuitry, and players like MGE UPS Systems, Powerware and American Power Conversion (APC) disclosed new activities in the UPS arena.
Power MOSFET makers Infineon, Philips, Siliconix and Toshiba had plenty to offer. For instance, Infineon introduced its optiMOS2 30 V n-channel MOSFET family with a maximum on-resistance of 3.3 mΩ at a gate voltage of 4.5 V in a high-performance superSO8 package. Philips Semiconductor has expanded its µTrenchMOS line with a number of low on-resistance parts for use in wireless communications gadgets. Separately, Philips has also launched p-channel MOSFETs with 20 and 30 VDS rating with 50 mΩ on-resistance at 4.5-V gate voltage. Concurrently, the manufacturer has developed what it claims is the world's first sub one milliOhm MOSFET. Philips has broken new ground in the field of MOSFET technology in the race to offer the lowest on resistance Rds (on) of 1 mΩ in a TO220-type package. The achievement was realized primarily due to combination of packaging with the use of copper clip technology. Normally, MOSFETs are connected to the top of a chip by using a weld where the wire bond would go. With copper clips, instead of connecting to a single point, the entire surface of the chip is connected, improving current distribution and thermal properties.
Likewise, Siliconix revealed new TrenchFET Gen II MOSFETs for synchronous buck converters. Two new devices—Si4336DY and Si7336DY—raise the bar on figure-of-merit (FOM) and gate charge ratio. The FOM, which is on-resistance times gate charge, is 83 mΩnC, and the gate charge ratio is 0.515. The maker asserts that the FOM offers 13.5% improvement over the next-best S08 devices. By similar comparison, the gate charge ratio has been improved by 35.6%, according to Siliconix. Both devices are designed for operation at up to 1 MHz and feature a typical Rds(on) of 2.6 mΩ at 10-V gate drive and typical gate charge of 32 nC at 4.5-V gate voltage.
Unlike others, Toshiba America Electronic Components (TAEC) highlighted its high-voltage MOSFETs, designated TO-220SIS, using its advanced Π-MOS IV and VI process technologies. The turn-off time for the Π-MOS VI-based 500-V and 600-V MOSFETs is 10% faster than previous generation transistors, while 900 V using the Π-MOS IV process offers a 15% improvement in switching time. Targeting ac-dc power supplies and ballast lighting applications, the TO-220SIS MOSFETs come in packages that offer isolation and a reduced height of 2.8 mm.
On the power IC front, STMicroelectronics revealed the first member of a new line of multiphase PWM controllers for latest Intel CPUs. Designed for VRM/VRD 10.0 specifications, the dual-phase L6710 integrates on a single chip a control loop with high current driver, control logic and protection. Housed in a TQFP44, the L6710 includes a 6-bit DAC that supports on-the-fly VID code changes. The company also indicated that it’s readying a single chip 3-phase version for introduction early next year, targeting VRD 10.1 specs.
In planar magnetics, TT Electronics MMG has developed an integrated suite of software design tools for E/E and E/I planar ferrite cores. Called NeoPlanes, the developer claims that it’s the only planar magnetics design tool of its kind for the IEC standard 18-mm, 22-mm and 32-mm E/E and E/I size ferrite cores. The kit consists of planar winding elements, each containing a multilayer printed circuit wiring. Featuring special interconnections and 12 surface solderable pads, the design kit’s elements facilitate stacking of boards for transformer and inductor assemblies.
“The NeoPlanes design kit will enable engineers to experiment with different configurations when specifying planar transformer designs,” said Brian Wiese, MMG’s director of marketing. “It offers an extremely cost-effective option to planar magnetics design,” added Wiese.
Likewise, to address the low-profile, high-current and high-efficiency requirements of emerging dc-dc converter modules, Payton Planar Magnetics displayed its newest high-current SMT planar transformer. Measuring 1.18 in. x 1.062 in. x 0.338 in., Payton’s SMT planar transformers offer 500 W capability with 24-V, 48-V or 390-V input and 1.2-V to 48-V output. Other features include low EMI, excellent repeatability and low weight, with operating temperature up to 130°C at full power.