SiC, Motor Drivers, Current Transducers & more - New Product Highlights from PCIM
This year’s PCIM power electronics exhibition, held in Nuremberg, Germany, attracted over 10,000 visitors from around the world, a slight increase on last year’s figures. As in previous years, all the leading manufacturers of power electronics components and equipment were present to showcase their latest offerings. Here are our highlights of the best new products debuted at the show.
By Sally Ward-Foxton
PCIM 2017 attracted over 10,000 visitors
SiC Mass Production
Infineon announced that the company’s first all-SiC power module, the Easy 1B, has gone into volume production, a year after the module was first announced at last year’s PCIM. The Easy 1B is a half-bridge/booster module with a low RDS(ON) of only 45mΩ, suitable for drives, solar inverters and welding equipment.
The company also revealed details of upcoming SiC products. The Easy 2B half-bridge module is a larger device than the 1B with enhanced RDS(ON) of 8mΩ per switch, designed for fast switching applications such as solar inverters, quick-charging systems and UPS. There is also a new 62mm half-bridge SiC module offering even higher power capability with RDS(ON) of 6mΩ for medical and railway auxiliary power supplies. The company will also offer discrete SiC MOSFETs in TO-247 3- and 4-pin packages, as well as bare die.
While SiC transistors offer higher efficiency, increased power density and smaller footprints, they are still much more expensive than comparable silicon products.
“For today and tomorrow, and I’m tempted to say, for ever, the comparable SiC device will be more costly than silicon,” said Peter Wawer, Division President for Industrial Power Control at Infineon. “But SiC is at the beginning of high volume manufacturing where silicon is already several decades behind. We will see a significant price decline; we expect that this gap will close to a certain extent, but will always remain.”
Wawer went on to explain that there are still financial savings to be made in terms of system costs, since SiC products require less complex surrounding circuitry. For some applications, this cost benefit is already apparent, he said.
Compressible Thermal Interface
Panasonic Automotive and Industrial Systems Europe had a much larger booth than last year, showing off the company’s semiconductors, passive components and thermal management solutions.
Panasonic’s SoftPGS thermal interface material comes in sheets the size of popular IGBT modules
Demonstrated on the booth was the company’s pyrolytic highly oriented graphite sheet (PGS) material, a thermal interface material which is one of the thinnest in the world. The latest materials in this group have impressive thermal conductivity of 1950 W/mK, five times higher than copper. There is now a brand new soft version called SoftPGS which offers lower thermal conductivity of 400 W/mK in the X-Y direction (28 W/mK in the Z direction) but is only 200µm thick and 40% compressible, ideal for protecting sensitive electronics from heat damage. Standard sized sheets of SoftPGS are available to match popular IGBT modules on the market. Panasonic say SoftPGS is less labour-intensive to install than thermal greases or phase change materials.
Higher Voltage Gate Drivers
Power Integrations introduced a new gate driver IC that supports 1700-V IGBTs, a new addition to its SCALE-iDriver IC family which previously only went up to 1200V.
PI’s SCALE-iDriver IGBT driver now supports 1700 V operation
The SCALE-iDriver range is a family of galvanically isolated single-channel gate drivers which use the company’s FluxLink magneto-inductive technology to communicate between the primary side and secondary side circuits. This reduces the switching losses found in comparable products that use opto-coupler technology. FluxLink can communicate through the new part’s >0.4mm of internal isolation, and the part offers >9.5mm of creepage.
With the new higher voltages, the SCALE i-Driver family is now suitable for 400VAC and 690 VAC line applications, as well as three-level photovoltaic inverters and photovoltaic arrays using the new 1500V DC bus standard.
Fast Current Transducers
The newly-introduced LEM GO family of current transducer ICs based on its state of the art Hall sensor ASIC, which offers a good tradeoff between accuracy and speed. These devices are a level above simple open loop Hall effect transducers – they feature primary integrated conductors for gradient measurement, which also provide immunity against any external magnetic fields from the environment.
The LEM GO range of current transducers responds quickly and accurately
There are 8 parts in the GO range for measuring nominal 4 A up to 30 A (DC, AC or pulsed); they can measure up to 2.5x the nominal current and withstand up to 200 A peak overload current for 1 ms. Response time is 2.0 µs and accuracy is as good as 1.3%.
The GO range includes an internal overcurrent detection feature which responds quickly (within 2.1 µs), triggered by currents at almost ±3x nominal current (accuracy 10%), plus an external overcurrent detection which is slower (10 µs response) but more accurate (5%), and the threshold can be set by two resistors.
A combination of the GO series’ response speed and overcurrent detection makes it suitable for AC drives. The parts come in SO8 or SO16 SMD packages.
Sinusoidal Motor Drivers
Allegro Microsystems previewed a couple of motor driver ICs for fans, both for 3-phase sensorless BLDC motors control. The A5931incorporates sinusoidal drive to minimise audible noise and vibration. Also featuring 180° sinusoidal drive, the A5932 is designed to drive external N-channel power MOSFETs in server fan applications.
Allegro’s APS13568 is a magnetic sensor and LED driver in one package
Also on show was Allegro’s latest position sensor, the APS13568, a Hall effect sensor IC that acts as a magnetically-operated light switch for car sun visors and refrigerator doors. The part combines an ultrasensitive, omnipolar, micropower Hall-effect sensor switch with a linear programmable current regulator providing up to 150 mA to drive high brightness LEDs.
Entry Level Oscilloscope
And finally: on the Rohde & Schwarz booth, the company showcased the highlights of its oscilloscope portfolio, including the recently introduced RTB2000, an entry level oscilloscope for the education, R&D and production markets. This new oscilloscope incorporates features previously only found on more expensive equipment, such as a 10.1” capacitive touch screen, 10-bit vertical resolution and a 10 Msample per channel acquisition memory. It comes in two- or four-channel models with bandwidths between 70 and 300 MHz.
The Rohde & Schwarz RTB2000 has high end features with an affordable price tag