IR’s New Mid-Power SmartRectifier™ IC Boosts Overall System Efficiency One Percent Using 75 Percent Fewer Components

EL SEGUNDO, Calif. — International Rectifier, IR®(NYSE: IRF), a world leader in power management technology, today introduced the IR1166 SmartRectifier IC for AC-DC power converters used in laptops, mini-PCs, LCD and PDP televisions, game systems, home theater audio, motor drive, and other digital computing and home entertainment systems. Enabling smaller and cooler supplies, the eight-pin IR1166 IC simplifies the design of mid-power secondary synchronous rectification (SR) circuits of resonant half-bridge converters and flyback converters designed for 50-150W discontinuous conduction mode (DCM), critical conduction mode (CrCM), and continuous conduction mode (CCM).

“IR’s new SmartRectifier IC uses a new technique for precise, direct sensing of voltage thresholds across the SR MOSFETs, allowing fast, accurate control to minimize power losses in mid-power flyback circuits. In contrast, traditional complex and bulky current transformer control circuits waste energy because of the large reversing currents required to sense polarity shifts through the SR MOSFETs,” said Mario Battello, marketing manager at International Rectifier.

“Compared to discrete solutions, IR1166S increases overall system efficiency by one percent while using 75 percent fewer components, and allowing a 25 percent reduction in SR system cost,” Battello added.

The IR1166 SmartRectifier IC works independently from the primary control and enables synchronous rectification so it can be used in a variety of transformer switching modes and applications with capacitive output filters. Furthermore, when “burst mode” occurs on the primary side, the secondary side remains unaffected, complying with California Energy Commission (CEC) 80Plus™ and “1W Standby.”

Optimized Chipset Solution

This new device, based on IR’s proprietary high voltage IC (HVIC) technology, is compatible with all MOSFET gate types, and offers a direct connection to a wide range of 40V to 200V SR MOSFETs. When used with IR’s standard and logic-level HEXFET® power MOSFETs, the new IC reduces losses dissipated in the SR MOSFET by 50 percent, reducing the number of MOSFETs needed in the circuit or enabling the use of smaller packages, such as surface mount SO-8 parts. These optimized MOSFETs work with the IR1166 to create a “total chipset solution” to further maximize efficiency and power density in SR circuits.

In addition to the SmartRectifier IC, there will be an IRAC1166-100W 100W flyback converter reference design available that operates in CrCM. This reference design demonstrates the SmartRectifier features by resolving the output rectification function using a combination of one IR1166SPbF IC and two IRF7853 (SR) MOSFETs in parallel. The entire solution uses only three SO-8 packages for low-side output rectification and requires no heatsink.

The new IC is available immediately in an SO-8 package and soon in DIP-8 package, which are both lead-free (PbF) and compliant with the Restriction of Hazardous Substances Directive (RoHS).

Part Number Package VCC
(V)
VFET
(V)
Switching Frequency Max.
(kHz)
Gate Drive +/-
(A)
VGATE Clamp
(V)
Sleep Current Max.
(µA)
IR1166SPbF SO-8 20 <=200 500 +1/-3.5 10.7 200
IR1166STRPbF SO-8 20 <=200 500 +1/-3.5 10.7 200
IR1166PbF DIP-8 20 <=200 500 +1/-3.5 10.7 200

Example MOSFETs to use with IR1166 Smart Rectifier

Part Number VDSS
(V)
RDS(on) max @ 10V
(mOhms)
Package
IRFB4110 100 4.5 TO-220
IRF7853 100 18 SO-8
IRFB4227 200 24 TO-220

Design Tools

In addition to data sheets, application notes and technical papers available on the Web at www.irf.com, SmartRectifier online design software is available on IR’s myPower website. Designers simply enter application conditions and performance requirements to obtain recommended IC and MOSFET chipsets that can then be sorted by performance and system cost. Daughter cards are also available that offer a fast and simple way to compare the efficiency and simplicity of IR’s SmartRectifier solution to alternative design approaches in existing designs.

Availability and Pricing

Unit pricing is US $0.70 each for the IR1166SPbF, IR1166STRPbF and IR1166PbF, in 10,000-unit quantities. Production quantities are available immediately. Pricing is subject to change.