This document introduces the BD9850FVM and BD9851EFV, two switch power supply controllers, which are respectively suitable for 1-channel and 2-channel switch power supply, with a maximum switching frequency of 2 MHz and 3 MHz, high-precision reference voltage, undervoltage lockout and thermal shutdown functions, and MSOP8 and HTSSOP-B20 packages.
The BD9850FVM is a single‑channel DC/DC step‑down switching regulator controller designed for high‑frequency operation up to 2 MHz. It provides a compact MSOP8 package and includes built‑in protection functions such as UVLO, thermal shutdown, and optional standby control.
The document outlines the device’s electrical characteristics, pin assignments, and recommended circuit configurations. It also details the reference voltage block, oscillator, error‑amp, PWM comparator, and FET driver blocks, along with guidance on soft‑start, standby, short‑circuit protection, and other safety features.
| Oscillation frequency range | 100 kHz to 2 MHz |
|---|---|
| Package | MSOP8 |
| Operating temperature | -40 °C to 85 °C |
| Power supply voltage (typical) | 4 V to 9 V |
| Power dissipation | 587 mW |
| Maximum junction temperature | +150 °C |
| Storage temperature range | -55 °C to +150 °C |
The BD9850FVM can be adapted for a switching frequency up to 2 MHz.
The reference voltage has an accuracy of ±1 %.
The CTL/SS pin is used to enable or disable the output for standby control.