HM2802 datasheet(10/12 Pages) HMSEMI

10 / 12 page

30V 1.5A 1MHz Sync Step-Down Dimmable LED Driver

Inductor Selection

Select the appropriate inductance value according to different number of series lamp groups. For most applications,

4.7 to 10μH are recommended. Small size and better efficiency are the major concerns for portable device, such as

HM2802 used for mobile phone.

When selecting the inductor, the inductor saturation current should be rated as high

as the peak inductor current at maximum load, and respectively, maximum LED current.

Output Capacitor Selection

The device is designed to operate with a wide selection of ceramic output capacitors. The selection of the output

capacitor value is a trade-off between output voltage ripple and capacitor cost and form factor. In general, capacitor

values of 10µF up to 22µF can be used. For better voltage filtering, ceramic capacitors with low ESR are recommended.

X5R and X7R types are suitable because of their wider voltage and temperature ranges.

Input Capacitor Selection

For good input voltage filtering, low ESR ceramic capacitors are recommended. A 10µF ceramic input capacitor is

sufficient for most of the applications. For better input voltage filtering and EMI reduction, this value can be

increased. The input capacitor should be placed as close as possible to the input pin of the converter.

HM2802 Datasheet(PDF) 10 Page - Shenzhen Huazhimei Semiconductor Co., Ltd