BU4221FVE-TR

Overview

The BU4221FVE-TR is a CMOS voltage detector IC from Rohm Semiconductor featuring an adjustable output delay timer. It provides a low-active open-drain reset signal with a typical under-voltage detection threshold of 2.1V and ±1% precision. The device operates within a supply voltage range of 0.7V to 7V, drawing ultra-low current (0.55µA typical). It includes hysteresis equal to VDET x 0.05 and supports an external delay circuit resistance up to 10.0MΩ. The component functions reliably across an industrial temperature range of -40°C to +125°C.

Feature Summary

• Adjustable delay timer allows flexible timing configuration via external components
• Ultra-low power consumption suitable for battery-operated systems
• High accuracy voltage detection ensures reliable system supervision
• Open-drain output facilitates interface compatibility with various logic levels

Applications

• Portable electronic devices requiring extended battery life
• Microprocessor and microcontroller system supervision
• Industrial control equipment operating in harsh environments
• Automotive electronics non-critical subsystems

Procurement Notes

Verify the specific ordering suffix matches the required tape-and-reel quantity. Confirm RoHS compliance status for environmental regulations. Check the latest supply status as this model may be subject to last-time-buy notices. Ensure the VSOF5 package dimensions fit the target PCB footprint constraints.

Selection Notes

Select this component when precise voltage monitoring with customizable reset delays is required. The wide operating voltage range accommodates various power rails. Consider the thermal performance limits if deployed in enclosed high-temperature enclosures. Verify that the open-drain output capability aligns with the downstream logic requirements.

Part Context

This part belongs to the BU42xx series of CMOS voltage detectors designed for general-purpose power management. The series emphasizes low current draw and compact packaging solutions like VSOF5. It serves as a supervisory circuit alternative to more complex PMICs in cost-sensitive applications.

Replacement Considerations

BD5221G-1 is documented as a recommended replacement with the same pinout. Verify electrical parameter compatibility before substitution.