Boost LED Driver IC delivers sub-Ás PWM dimming.
February 10, 2012 -
Used for LCD backlighting, 3-channel HV9989 features PWM dimming control algorithm that regulates each channel's output current down to sub-Ás dimming pulses. This permits dimming at frequencies outside audible range without shift in color correlated temperature. Powered by 40 V linear regulator, IC drives boost or SEPIC converters in continuous or discontinuous conduction mode. Three 1 MHz transconductance amps with tri-state outputs close feedback loops and accurately control LED current.
(Archive News Story - Products mentioned in this Archive News Story may or may not be available from the manufacturer.)
|Original Press release |
1235 Bordeaux Dr.
Sunnyvale, CA, 94619
Three Channel LED Driver from Supertex Delivers Submicrosecond PWM Dimming for LCD Backlighting Applications
HV9989 Features Patented Control Algorithm
SUNNYVALE, Calif., - Supertex, Inc. (Nasdaq GS: SUPX) today introduced HV9989, a three channel, boost LED driver integrated circuit (IC) designed to drive LEDs in LCD backlighting applications. It features Supertex's patented PWM dimming control algorithm that individually regulates each channel's output current down to sub-microsecond dimming pulses, which permits dimming at frequencies outside the audible range (>20kHz) without any shift in the "white point" or the colorcorrelated temperature. It drives strings of either RGB LEDS or multiple strings of white LEDs.
HV9989 drives boost or SEPIC converters in either continuous-conduction mode (CCM) or discontinuous-conduction mode (DCM). It features independent shortand open-circuit protection for each channel and three 1MHz transconductance amplifiers with tri-state outputs to close feedback loops and accurately control the LED current. It is powered by a built-in 40V linear regulator.
"HV9989 can operate with very high dimming frequency and deliver an over 10,000:1 dimming ratio because of its patented PWM dimming method," states Stephen Lin, Vice President of Marketing at Supertex. "The IC combines excellent line and load regulation in a multi-channel driver IC to reduce board space and system cost in LCD backlighting applications like flat screen TVs and monitors."
The HV9989 is available in a 40-lead QFN package (HV9989K6-G). Samples are available from stock. Lead-time for production quantities is 4-6 weeks ARO. Pricing is US$3.78 for the HV9989K6-G in 1K quantities.
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, printer and display, industrial and telecommunication industries. Supertex product, corporate and financial information is readily available at www.supertex.com.