White LED step-up converter integrates Schottky diode

Camarillo, Calif.—Semtech Corp. has launched the SC4509, a step-up converter for white LED backlight applications with an integrated Schottky diode in a 2 x 2 x 0.8 mm package.

The SC4509 can drive up to five white LEDs in series. The device's built-in Schottky diode saves board space and reduces costs while still providing efficiencies of more than 80%.

To simplify control of the backlight, the SC4509 features a combination enable and PWM dimming pin that allows the user to turn the device on and off, or to apply a PWM dimming signal of up to 10-kHz to control the output current level and dim the LEDs.

The input voltage range for the SC4509 is 2.7V to 10V, and the device can output up to 20V at 30mA. The device operates with a 1.2 MHz constant switching frequency. The SC4509 is available in either an MLPD-8 or SOT-23 package, both of which are RoHS compliant.

Pricing: $0.37 each in 1,000-piece lots.
Availability: The SC4509 (order code: SC4509WLTRT for MLP 2×2 package) and (order code: SC4509SKTRT for SOT-23 package) are available immediately in production quantities.
Datasheet: click here.

Semtech Corp., 1-805-498-2111,

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