S-8521C36MC-BTVT2G

Overview

The S-8521C36MC-BTVT2G 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 achieve high efficiency across varying load conditions. The device operates within an input voltage range of 2.5V to 10V and supports a switching frequency of 60kHz. It features a duty ratio capability up to 100% and includes a soft-start circuit to prevent startup overshoot. The component is housed in a compact SOT-23-5 package and is rated for an operating temperature range of -40°C to +85°C.

Feature Summary

• Supports automatic switching between PWM and PFM control modes to maintain high efficiency under light loads
• Integrates a soft-start circuit to suppress output voltage overshoot during power-on
• Provides linear duty ratio variation from 0% to 100% for precise regulation

Applications

• Portable electronic devices requiring efficient power management
• Battery-powered equipment utilizing single-cell lithium-ion batteries
• General-purpose DC-DC converter circuits with space constraints

Procurement Notes

Verify the specific suffix 'BTVT' against the official datasheet to confirm pinout and marking variations. Confirm RoHS compliance status as per the latest manufacturer statement. Check for obsolescence notices or PCN updates regarding material changes. Ensure external component selection matches the 60kHz switching frequency requirements.

Selection Notes

Select this controller when designing non-synchronous buck converters requiring high efficiency at light loads. It is suitable for applications where input voltage varies between 2.5V and 10V. Consider the S-8520 series if fixed PWM control is preferred over the hybrid PWM/PFM mode. Ensure the external MOSFET can handle the peak currents generated by the 60kHz operation.

Part Context

This part belongs to the S-8520/8521 series of CMOS step-down switching regulator controllers. The S-8521 variant specifically distinguishes itself by offering dual-mode control (PWM/PFM), whereas the S-8520 series relies solely on PWM control. Both share similar internal architectures including error amplifiers and reference voltage sources.

Replacement Considerations

The S-8520C36MC-BTVT2G serves as a functional alternative if PWM-only control is acceptable. Verify that the replacement maintains the same SOT-23-5 footprint and electrical characteristics.