Products, Materials + Tools | Jan 05, 2011

LED Driver from Supertex Delivers Superior Current Accuracy with Integrated MOSFET

Supertex, a recognized leader in high voltage analog and mixed signal integrated circuits (ICs), today introduced HV9967, an open loop, average-mode current control LED driver IC that operates in a constant off-time mode. The IC includes a 60V, 0.8 ohm MOSFET that can be used as a stand-alone buck converter, or connected as a source driver output for driving an external MOSFET, such as Supertex DN2450, to operate at offline AC line voltages.

Features:
• 3% accurate LED current
• Integrated 60V 0.8Ω MOSFET
• Small outline MSOP-8 package
• Low sensitivity to external component variation
• Cascode connection with a 500V depletion-mode
• MOSFET
• Single resistor LED current setting
• Fixed off-time control
• PWM dimming input
• Output short circuit protection with skip mode
• Over-temperature protection

Applications:
• DC/DC or AC/DC LED driver applications
• RGB backlighting of flat panel displays
• General purpose constant current source
• Signage and decorative LED lighting
• Chargers

The HV9967 features a proprietary control method that achieves fast, accurate LED current control through sensing only the switch current. The IC delivers LED current accuracy of +/-3% without sensitivity to external component variation. It utilizes average-mode current control, which doesn’t produce a peak-to-average error, and therefore greatly improves LED current accuracy and line and load regulation without requiring loop compensation or direct current sensing. The HV9967 also includes internal over-temperature and short circuit protection, and a PWM dimming input.

“With its unique current control method, HV9967 offers solid-state lighting designers the benefits of high current accuracy and consistency for extended LED lifetimes,” states Hernan DeGuzman, Vice President of Marketing for Supertex. “This IC is quite simple to use, and its accuracy is virtually insensitive to the tolerances of external passive components in the application circuit.”

The HV9967 is available in an 8-lead MSOP package (HV9967MG-G). The part is Green and RoHS compliant. Samples are available from stock. Lead-time for production quantities is 4-6 weeks ARO. Pricing is US$.80 each for the HV9967MG-G in 1K quantities.

About Supertex:
Supertex, Inc. is a publicly held mixed signal semiconductor manufacturer, focused in high voltage analog and mixed signal products for use in the medical, LED lighting, display, industrial, and telecommunication industries. Supertex product, corporate and financial information is readily available at www.supertex.com.

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