S-8520F31MC-BNQT2G

Overview

The S-8520F31MC-BNQT2G is a CMOS step-down switching regulator controller manufactured by ABLIC Inc. It utilizes Pulse Width Modulation (PWM) control to maintain stable output voltages. The device operates within an input voltage range of 2.5V to 16V and features a fixed output voltage setting of 3.1V. It supports a maximum switching frequency of 300kHz and includes built-in soft-start functionality to prevent startup overshoot. The component is housed in a compact SOT-23-5 package and is rated for operation across a temperature range of -40°C to +85°C.

Feature Summary

• Integrates PWM control circuitry with linear duty ratio variation from 0% to 100% for low-ripple power delivery
• Includes internal error amplifier and soft-start circuit to ensure stable startup without voltage overshoot
• Operates as a standalone controller requiring only external Pch MOS FET, coil, capacitors, and diode

Applications

• Portable electronic devices requiring efficient step-down power conversion
• Battery-powered equipment needing regulated voltage supply
• General-purpose DC-DC converter circuits in consumer electronics

Procurement Notes

Verify the specific suffix BNQT2G against official ABLIC documentation to confirm tape-and-reel packaging and marking codes. Ensure compatibility with existing PCB footprints for the SOT-23-5 package. Confirm that the fixed 3.1V output aligns with system requirements, as this variant lacks adjustable output options. Check for obsolescence status or alternative recommendations from the manufacturer before finalizing procurement plans.

Selection Notes

Select this component when a fixed 3.1V output is required for step-down applications. It is suitable for designs prioritizing simplicity over adjustable voltage ranges. Consider the 300kHz switching frequency for balancing efficiency and passive component size. Verify that the external components can handle the current demands, as the IC controls rather than supplies the load current directly.

Part Context

This part belongs to the S-8520/8521 series of CMOS step-down switching regulator controllers. The S-8520 series specifically focuses on PWM control for consistent performance under varying loads. It shares architectural similarities with other ABLIC power management ICs but is distinct in its fixed-output configuration and specific pinout arrangement for the SOT-23-5 package.

Replacement Considerations

Direct substitutes include other parts from the S-8520 series with matching output voltages and packages, such as the S-8520F31MC-BNAT2U. Cross-reference pinouts and electrical specifications carefully. Generic PWM controllers may require additional external components or different biasing configurations.