HV9911 LED driver ICs from Supertex Inc., Sunnyvale, Calif., give good current accuracy and a wide input voltage range (9 to 250 Vdc). They are designed specifically for dc/dc applications such as RGB backlighting, automotive lighting, and battery-powered LED lamps.

The closed-loop, switched-mode LED driver ICs include an internal transconductance operational amplifier for tighter line and load regulation of LED current and good transient response to PWM dimming. The ICs can be synchronized to prevent subharmonic oscillations in applications with multiple LED drivers. The IC operates in fixed frequency or fixed off-time modes for use in converter topologies such as boost, fly-back, and buck.

The HV9911 also has slope compensation for wider operating ranges in fixed-frequency mode, and an internal regulator for use in low and high-voltage applications. The HV9911 comes in a 16-lead SOIC package (HV9911NG-G) and complies with Green and RoHS regulations.