BU46K404G-TL

Overview

The BU46K404G-TL is a voltage detector IC from the ROHM BU45/BU46 series, designed for monitoring single-input power supplies. It features a CMOS output and operates within a supply voltage range up to 6 V. The device detects a threshold voltage of 4 V with an accuracy of ±1%. It includes a built-in counter timer delay circuit providing a fixed reset delay time of 400 ms, eliminating the need for external capacitors. The component consumes a typical operating current of 2.8 µA and functions across a temperature range of -40°C to +105°C. It is housed in an SOT-23-3 package.

Feature Summary

• Built-in counter timer delay circuit eliminates the requirement for external timing capacitors
• High detection accuracy of ±1% ensures precise voltage monitoring
• Low current consumption design suitable for battery-powered applications
• CMOS output type provides direct interface compatibility with digital logic

Applications

• Monitoring microprocessor power supply voltages
• Battery-operated electronic devices requiring low quiescent current
• Portable equipment with limited power budgets
• General-purpose voltage supervision in consumer electronics

Procurement Notes

Verify the specific suffix TL against official ROHM documentation to confirm tape-and-reel packaging specifications. Confirm that the SOT-23-3 package variant matches your PCB footprint requirements. Check for RoHS compliance status in the latest datasheet revision. Ensure the obsolete or NRND status does not conflict with long-term production plans. Validate humidity sensitivity classification before storage and handling procedures.

Selection Notes

Select this component when a fixed 400 ms delay is acceptable without external components. Choose based on the 4 V threshold requirement and ±1% accuracy tolerance. Consider the SOT-23-3 package size constraints. Evaluate the 2.8 µA current draw against system power budgets. Verify the 6 V maximum supply voltage aligns with the monitored rail.

Part Context

This part belongs to the ROHM BU45/BU46 series of highly accurate, low-current voltage detectors. These ICs are characterized by their integrated delay timers and compact packaging options. The series supports various threshold voltages and output types to accommodate diverse supervisory needs in portable and industrial applications.

Replacement Considerations

Publicly confirmed substitute: BD5235G-1. Note that the substitute uses an SSOP-5 package instead of SOT-23-3 and offers adjustable delay rather than fixed 400 ms. Verify pinout compatibility and electrical parameter alignment before substitution.