Product Review
SiC power MOSFET pushes past Si-based MOSFETs/IGBTs with lower losses, lower capacitance, easier drive
Bill Schweber1/17/2011 5:06 PM EST
Durham, NC—Pushing past silicon-based power MOSFETs and IGBTs, Cree, Inc. has introduced what they claim is an industry first: fully qualified and characterized silicon carbide (SiC) power MOSFETs. Compared to existing components, the vendor says these devices offer faster switching speeds, lower switching losses, easier drive, key specifications which are less temperature dependent, and no reverse recovery losses (aka "tail crunch").These MOSFETs compete with 900 V Si-based MOSFETs and 1200 V IGBTs, see Figure below.
The CMF2012SD series devices are designed for blocking voltages up to 1200 V, along with RDS(ON) of 80 mV at 25°C, and remaining below 100 mV up to maximum operating temperature (just a 20% increase). The MOSFETs are housed in industry-standard TO-247 packages, making them a form, fit, yet functionally superior replacement for available devices. Gate-drive requirements are simplified due to the low gate charge throughout the input-voltage range, with QG less than 100 nC, while losses are reduced due to forward drop (VF) below 2 V at 20 A load current.
According to John Palmour, Cree founder and CTO, in typical applications, these SiC-based MOSFETS result in system efficiency gains of two percentage points; he noted that in one well-designed solar-inverter application at Fraunhofer Institute (Freiburg, Germany), efficiency increased from 96% to 98%, in an application where even fractions of a percent are considered vital.
In addition, since the devices can operate at switching frequencies which are two to five times those of present dev ices, overall system design also benefit from smaller, lighter passive components (mostly in magnetics). Leakage current is under 1 μA, which contributes to system reliability, and remains fairly constant despite elevated reverse voltages or temperature increase. Switching losses are much less than Si-based MOSFETs of comparable ratings, see Figure below.
Pricing and availability: The Cree SiC-based MOSFETs are available now from distributors. They are priced at a premium compared to Si-based MOSFETs, commensurate with what the vendor believes are their component-level attributes, as well as circuit- and system-level benefits.
For more information, contact Cree, Inc. at http://www.cree.com/power.
|
|
|
|
|
Most Popular
Datasheets.com Parts Search
185 million searchable parts
(please enter a part number or hit search to begin)
Our technical library houses over 4,000 high-quality sponsored white papers, application notes, reference guides, use cases—all organized by company.
Rama Murthy
1/19/2011 9:09 PM EST
Besides spreading good white light, CREE has been the first to add the shine of a diamond to power mosfets.
Sign in to Reply
BCoates
4/1/2011 5:06 PM EDT
Hello Rama, I am conducting a search for one of my top clients focused on High Voltage IGBTs. I am offering a significant finders fee if someone is able to help me with this position. Are you available for a phone call next week?
Sign in to Reply
bcarso
1/20/2011 12:27 PM EST
It's nice to see these coming online finally, and depsite the expense they should see a healthy market, especially in solar power apps. One comment: No mention is made of up-and-coming GaN devices---of course they are just becoming available, and at relatively modest power levels, so perhaps fair enough.
In the beginning of the piece, the on resistance is expressed in mV. Of course that is a typo and should be milliohms.
Sign in to Reply
Etmax
1/21/2011 8:52 AM EST
80mOhm for a 1200V device, now that's something to crow about. MOSFET's have around an Ohm and IGBT's a a fixed ~2V loss which this device wouldn't see until ~25A. Sounds almost too good to be true. I want one :-)
Sign in to Reply
Jim Stockton
12/23/2011 8:21 AM EST
I wish they would scale it down to DPAK
Sign in to Reply