S-8521A36MC-AXVT2G

Overview

The S-8521A36MC-AXVT2G is a CMOS step-down switching regulator controller from the S-8520/8521 series, manufactured by ABLIC Inc. It utilizes PWM/PFM switching control to ensure high efficiency across wide load ranges. The device operates with an input voltage range of 2.5 V to 10 V and supports a maximum switching frequency of 375 kHz. Packaged in a compact SOT-23-5 (SC-74A) surface-mount format, it features a soft-start circuit to prevent startup overshoot and includes an enable function for power management.

Feature Summary

• Supports automatic switching between PWM and PFM control modes to maintain high efficiency under varying load conditions
• Integrates a soft-start circuit to prevent output voltage overshoot during initial power-up
• Features an error amplifier and oscillation circuit within a miniaturized package suitable for portable applications

Applications

• Battery-powered portable electronic devices requiring efficient DC-DC conversion
• Embedded systems utilizing external Pch MOSFETs or PNPs for step-down regulation
• Applications necessitating low standby current consumption through PFM mode operation

Procurement Notes

Verify the specific suffix AXVT against official ABLIC documentation to confirm tape-and-reel packaging and marking codes. Confirm RoHS compliance status and check for any recent design changes or obsolescence notices via manufacturer PCNs before finalizing procurement plans.

Selection Notes

Select this component when designing a non-synchronous buck converter requiring flexible control modes. Ensure the external circuit includes a coil, diode, and capacitors as the IC acts only as a controller. Verify that the required output voltage and current capabilities are met by the external power stage components rather than the IC itself.

Part Context

This part belongs to the S-8521 Series, which offers PWM/PFM switching control. Unlike the S-8520 series which uses fixed PWM, the S-8521 automatically switches to PFM at light loads to improve efficiency. This series is designed for use with external power transistors to create cost-effective step-down regulators.

Replacement Considerations

The S-8520E22MC-BJH-T2G serves as a functional substitute within the same family, though it lacks PFM capability. Verify pin compatibility and control mode requirements before substitution.