BU4221G-TR

Overview

The BU4221G-TR is a CMOS voltage detector manufactured by ROHM Semiconductor, designed for monitoring single-channel power supply voltages. It features a fixed detection threshold of 2.1 V with an accuracy of 1%. The device operates within a supply voltage range up to 7 V and supports an adjustable reset delay time. It provides an open-drain output and functions reliably across an extended temperature range from -40 °C to +125 °C. The component is housed in a compact SSOP-5 surface-mount package.

Feature Summary

• CMOS technology ensures low current consumption and high reliability for voltage supervision tasks.
• Fixed 2.1 V threshold voltage provides precise detection without external resistor adjustments.
• Adjustable reset delay allows customization of the output timing relative to voltage recovery.
• Open-drain output configuration facilitates flexible interfacing with various logic families.

Applications

• Portable electronic devices requiring reliable power management
• Embedded systems needing simple voltage supervision
• Industrial control circuits operating in harsh environments

Procurement Notes

Verify the specific revision level and packaging details when ordering, as the BU4221G-TR may be subject to lifecycle changes such as NRND status. Confirm compatibility with your PCB footprint for the SSOP-5 package. Ensure that the adjustable reset delay requirements align with your system's startup sequence before finalizing procurement. Check for any RoHS compliance documentation relevant to your region's regulations.

Selection Notes

Select this component when a fixed 2.1 V threshold is required for single-supervision applications. The adjustable reset delay offers flexibility compared to fixed-delay alternatives. Consider the SSOP-5 package size constraints and the open-drain output capability for interface matching. Evaluate the -40 °C to +125 °C operating range against your environmental conditions to ensure adequate thermal performance.

Part Context

The BU4221G-TR belongs to the BU42(43)xxG series of supervisory circuits from ROHM Semiconductor. This family focuses on CMOS voltage detectors with various threshold options. The part is categorized under PMIC - Power Management ICs, specifically within the Supervisory Circuits subcategory. It shares design characteristics with other members of the BU42 series, differing primarily in threshold voltage and package variations.

Replacement Considerations

Direct substitutes include other ROHM parts from the BU42 series with similar thresholds, such as the BU4211G-TR (1.1 V threshold) or BU4232G-TR (3.2 V threshold), if threshold adjustment is permissible. Cross-manufacturer replacements require verifying pinout compatibility, threshold accuracy, and output drive capabilities. Always consult official datasheets for electrical parameter equivalence before substitution.