S-8521A32MC-AXRT2G

Overview

The S-8521A32MC-AXRT2G is a CMOS step-down switching regulator controller from the S-8521 series, manufactured by ABLIC Inc. It operates with an input voltage range of 2.5V to 10V and features PWM/PFM switching control. The device supports a maximum switching frequency of 60kHz and delivers a fixed output voltage of 3.2V. Designed for surface-mount installation in a SOT-23-5 package, it functions within a temperature range of -40°C to 85°C.

Feature Summary

• Supports automatic switching between PWM and PFM control modes to maintain high efficiency across varying load conditions.
• Integrates a soft-start circuit to prevent output voltage overshoot during startup.
• Provides linear duty ratio variation from 0% to 100% for low-ripple power delivery.

Applications

• Battery-powered portable electronic devices
• General-purpose DC-DC conversion circuits
• Embedded systems requiring efficient step-down regulation

Procurement Notes

Verify the specific suffix AXRT2G against official ABLIC documentation to confirm tape-and-reel packaging and marking codes. Confirm component status as not recommended for new designs due to potential minimum order quantity restrictions or lifecycle limitations before finalizing procurement plans.

Selection Notes

Select this controller when a fixed 3.2V output is required from a 2.5V to 10V input source. Ensure external components such as Pch MOSFETs and inductors are compatible with the 60kHz switching frequency. Verify that the SOT-23-5 package fits the available PCB space and thermal requirements.

Part Context

This component belongs to the S-8520/8521 series of CMOS step-down switching regulator controllers. The S-8521 variant specifically offers flexible PWM/PFM control, distinguishing it from the fixed PWM S-8520 series. It is designed for applications demanding high efficiency and stable performance in compact form factors.

Replacement Considerations

Consult official substitution lists for equivalent fixed-output buck controllers. Verify pin compatibility and electrical specifications if considering alternatives from other manufacturers.

FAQ

What control modes does the S-8521A32MC support?

It supports both Pulse Width Modulation (PWM) and Pulse Frequency Modulation (PFM), automatically switching between them based on load conditions.

Is the S-8521A32MC a synchronous rectifier controller?

No, it is a non-synchronous controller that requires external Pch power MOS FETs or PNP transistors for operation.