Innovative iWatt SSL LED Driver Addresses Cost and Lifetime Issues in Price-Sensitive Retrofit Bulbs

  Innovative iWatt SSL LED Driver Addresses Cost and Lifetime Issues in
  Price-Sensitive Retrofit Bulbs

               - iW3626 enables up to 20% BOM cost savings^(1)

 - Configurable over-temperature derating ensures predictable bulb operating

             - Configurable PF control offers design flexibility

Business Wire

CAMPBELL, Calif. -- January 29, 2013

iWatt Inc., a leading provider of digital-centric power management integrated
circuits (ICs), today launched an innovative digital AC/DC solid state
lighting (SSL) LED driver platform designed specifically to address the key
issues of cost and lifetime in price-sensitive, non-dimmable, residential SSL
bulb applications. The first device in this new platform is the iW3626, a
single-stage driver with output power up to 10W for 60W-equivalent,
non-dimmable LED bulbs. The iW3626 allows SSL designers to reduce their bill
of materials (BOM) cost as much as 20%^(1) compared to competitive solutions
and is believed to be the first SSL LED driver to offer an on-chip,
user-configurable power factor correction (PFC) to manage the trade-off
between PFC and output current ripple. Additionally, an internal, configurable
over-temperature protection (OTP) and derating function enables a predictable
and reliable bulb operating life. This combination of features gives LED bulb
manufacturers a new approach for lower-cost, higher-performance, non-dimmable
SSL incandescent bulb replacement applications.

The iW3626 was developed in close cooperation with several iWatt key
customers, including Eastfield International Industries, Ltd., which has
designed the iW3626 into its next-generation, non-dimmable SSL bulb product

“The challenge with SSL bulbs is hitting the price point the market demands
with the long-term reliability consumers expect,” said Mr. Jacky Luo, director
of R&D Centre at Eastfield International Industries. “We chose iWatt’s iW3626
because it enables us to optimize our designs to the specific needs of our
customers and because of the built-in OTP derating. These features enable us
to ensure predictable, long operating life with a low BOM cost.”

Regulations around the world mandate performance requirements, such as PFC and
input harmonics and these regulations vary by country and by application. In
single-stage LED drivers, there is a correlation between improving PF and
increasing output ripple. The patent-pending, user-configurable PFC feature in
the iW3626 allows designers to configure the PF strength from > 0.7 to > 0.9,
enabling them to meet the various global mandates, while effectively managing
the trade-off between power factor and output ripple. This helps ensure the
required power factor can be achieved with low output ripple, minimizing both
heat and flicker, with no impact to overall cost or size.

The on-chip, configurable over-temperature protection and derating feature of
the iW3626 monitors the temperature inside the sealed SSL bulb. When thermal
conditions reach a point set by the system designer, the iW3626 LED driver
automatically reduces the current drive to the LEDs, lowering the power
dissipation and resulting in cooler overall operation. This reduces the risk
of thermal runaway and ensures the temperature rating of the electrolytic
capacitors in the system is not exceeded, thereby helping ensure predictable
bulb operating life. Additional built-in protection features include LED
open/short, input over-voltage, over-current, and current-sense resistor short

The iW3626 achieves up to 20% BOM cost savings via its highly integrated
design features. It allows FETs to be replaced with lower-cost, bipolar
junction transistors (BJTs), eliminating the need for high-voltage
electrolytic capacitors, and includes the configurable over-temperature
protection feature on board. Additionally, iWatt’s patented PrimAccurate™
primary-side control eliminates the need for a secondary-side regulator and
optical feedback isolator.

The iW3626 is packaged in a standard, low-cost, 6-lead SOT23 package, which
can be used in single-layer PC boards for additional cost savings and a
smaller design footprint.

“The biggest obstacles to mass consumer adoption of SSL LED bulbs have been
cost and predictable operating life,” said Hubie Notohamiprodjo, iWatt’s
director of marketing for SSL products. “The iW3626 LED driver offers a new
approach to reduce these barriers in non-dimmable applications, with features
such as configurable power factor correction and integrated over-temperature
protection, which, until now, were only associated with higher-cost driver

iW3626 Key Features

  *Output power: 10W (for 60W equivalent bulbs)
  *User-configurable power factor from > 0.7 to > 0.9
  *PrimAccurate primary-side control reduces solution size, lowers BOM cost,
    increases reliability
  *Up to 20% BOM savings^(1)
  *High efficiency > 85% at high line
  *Tight LED current regulation better than ± 5%
  *LED over-temperature protection and derating
  *Meets global standards, including European Union IEC61000-3-2^(2)
  *Small SOT-23 package

Pricing, Availability

The iW3626 is available now in production quantities. Samples are available at
$0.35 in 1000-piece quantities. Product brief is available: iW3626 Product

About iWatt Inc.

Privately-held iWatt Inc. is a leading provider of digital-centric power
management integrated circuits (ICs). iWatt’s innovative PrimAccurate
technology platform enables high performance, energy-efficient,
small-form-factor and cost-effective solutions for markets such as AC/DC power
conversion, LED SSL, and LED display backlighting. The company’s solutions are
designed into the products of leading global original equipment manufacturers
(OEMs). iWatt has shipped more than one billion power management ICs since
2007, including more than 400 million in 2011. The company is backed by
VantagePoint Capital Partners and Sigma Partners, two leading CleanTech
investors, and Horizon Ventures. The company is headquartered in Campbell, CA
with additional offices in Taipei, Taiwan; Seoul, Korea; Tokyo, Japan;
Shenzhen, China; and Hong Kong. For more information, visit or call +1 (408) 374-4200.

iWatt and the iWatt logo are registered trademarks and PrimAccurate is a
trademark of iWatt Inc. All other trademarks and registered trademarks are the
property of their respective owners.

(1) BOM cost comparison based on iWatt’s analysis of published typical
application circuits.

(2) European Power Supply Manufacturers Association standard - IEC 61000-3-2:

Note to Editors:

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iWatt Inc.
Scott Brown, +1-408-385-1954
Moody & Associates
Michelle Moody, +1-214-363-3460
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