UM1663S

Overview

The UM1663S is a highly integrated LED driver IC designed for driving up to ten white LEDs in series. It features a current-mode boost converter topology with an internal 38V/1A power switch. The device supports a wide input voltage range of 2.8V to 5.5V and operates at a fixed switching frequency of 1MHz. It utilizes PWM dimming control and is housed in a SOT-23-6 package, offering a compact solution for portable electronic applications requiring efficient LED regulation.

Feature Summary

• Integrates a current-mode boost converter with a high-voltage power switch
• Supports PWM dimming control for brightness adjustment
• Operates from a single low-voltage supply without external charge pump

Applications

• Portable consumer electronics
• Mobile phone flashlights
• Handheld devices with LED indicators

Procurement Notes

Verify the exact manufacturer designation as Union Semiconductor International Limited or Union Semiconductor (HK) Limited when sourcing. Confirm the package type is SOT-23-6 and that the component matches the specific electrical characteristics for 10-series WLED driving. Ensure documentation aligns with the official datasheet specifications regarding input voltage and switching frequency.

Selection Notes

Select this component for applications requiring a compact, single-inductor boost solution for multiple series-connected white LEDs. It is suitable for battery-powered devices where space constraints necessitate a small SOT-23-6 footprint. Consider the 1MHz frequency for minimizing passive component size while maintaining efficiency within the specified 2.8V to 5.5V input range.

Part Context

This part belongs to the family of highly integrated LED drivers from Union Semiconductor. It is specifically engineered for portable applications, combining power switching and control logic into a single chip. The design focuses on reducing external component count and board area compared to discrete solutions, targeting cost-sensitive mobile and handheld markets.

Replacement Considerations

No public confirmed substitute part numbers are available in the provided documentation. Cross-referencing requires matching the SOT-23-6 package, 1A switch current capability, 38V breakdown voltage, and 1MHz boost topology.