The BD9870FPS is a single-channel step-down switching regulator that integrates a Pch MOSFET capable of PWM operation at 900kHz, enabling use of a smaller coil, as well as circuitry that eliminates the need for external compensation – only a diode, coil, and ceramic capacitor are required – reducing board size significantly.
The BD9870FPS is a single‑channel step‑down switching regulator that integrates a P‑channel MOSFET, allowing PWM operation at 900 kHz and eliminating the need for external compensation components. Key features include a maximum switching current of 1.5 A, adjustable output voltage via external resistors, soft‑start of 5 ms, and built‑in over‑current and thermal shutdown protection.
The note provides electrical characteristics, recommended component values, PCB layout guidelines, and typical performance graphs. It also lists applications such as TVs, printers, DVD players, projectors, gaming devices, PCs, car audio/navigation systems, and other industrial equipment.
| Maximum switching current | 1.5 A |
|---|---|
| Switching frequency | 900 kHz (fixed) |
| Soft start time | 5 ms (fixed) |
| Input voltage range | 8.0 V – 35.0 V |
| Efficiency (typical) | 80 % – 88 % |
| Package | TO252S8-5 (surface‑mount) |
The regulator can handle up to 1.5 A of switching current.
The soft‑start time is fixed at 5 ms.
It is supplied in a TO252S8-5 surface‑mount package.
The device operates from 8.0 V to 35.0 V.