The SD42509 is a power LED driver chip with a maximum output current of 1A and an input voltage range of 6-20V. The chip has built-in temperature protection and current limiting circuits, and can drive multiple LEDs.
The SD42509 is a buck‑type LED driver IC that uses current‑mode control and a fixed 280 kHz switching frequency. It integrates a 0.25 Ω power MOSFET, over‑temperature protection and per‑cycle over‑current protection, delivering up to 1 A output current while maintaining load current variation within ±1 % over a wide input voltage range.
Typical applications include driving single or multiple white LEDs in lighting modules, with recommended external components such as input capacitors >10 µF, output capacitors ≥4.7 µF, and inductors around 47 µH for 1 A operation. The device is supplied in an SOP‑8‑225‑1.27 package and is intended for use in consumer and industrial LED lighting designs. This manual is written in Chinese.
| Maximum Output Current | 1 A |
|---|---|
| Input Voltage Range | 6 V–20 V |
| Switching Frequency | 280 kHz (fixed) |
| Internal MOSFET On‑Resistance | 0.25 Ω |
| Operating Temperature Range | -40 °C to 125 °C |
| Junction Temperature (Tj) | 150 °C |
| Per‑Cycle Over‑Current Protection | Enabled |
| Package Type | SOP‑8‑225‑1.27 |
The SD42509 can deliver up to 1 A of output current.
It operates with an input voltage between 6 V and 20 V.
Yes, it provides over‑temperature protection and per‑cycle over‑current protection.
The chip uses a fixed switching frequency of 280 kHz.