BU45K342G-TL

Overview

The BU45K342G-TL is a fixed-delay voltage detector IC from ROHM Semiconductor, designed for monitoring single-input power supplies. It features a threshold voltage of 3.4 V with an accuracy of ±1%. The device operates within a supply voltage range of 0.6 V to 6 V and includes a built-in reset delay timer of 200 ms, eliminating the need for external capacitors. It utilizes an open-drain output configuration and consumes a typical operating current of 2.8 µA. The component is housed in an SSOP-3 package and supports an extended operating temperature range from -40°C to +105°C.

Feature Summary

• Integrated counter timer delay circuit removes the requirement for external delay-setting capacitors
• High detection accuracy maintained at ±1% across the operational range
• Low current consumption design suitable for battery-powered applications
• Fixed reset delay time ensures consistent system initialization timing

Applications

• Microprocessor reset circuits requiring fixed delay timing
• Battery-operated electronic devices needing low standby current
• Portable equipment with limited board space for passive components
• Industrial control systems operating in wide temperature environments

Procurement Notes

Verify the obsolete status before procurement as this part is Not Recommended for New Designs (NRND). Confirm availability through authorized distributors or secondary markets. Ensure compatibility with existing PCB footprints and design specifications. Check for moisture sensitivity levels if storage conditions are uncertain. Validate that the open-drain output aligns with the target system's input requirements.

Selection Notes

Consider the BU45K342G-TL when a fixed 200 ms delay and 3.4 V threshold are required without external timing components. Evaluate the trade-off between its 2.8 µA current draw and the lower consumption of newer alternatives like the BD5234G-1. Assess whether the SSOP-3 package fits the mechanical constraints. Verify that the open-drain output interface matches the downstream logic level requirements.

Part Context

This component belongs to the BU45/BU46 series of voltage detectors, characterized by high accuracy and low power consumption. The series offers various threshold voltages and delay options. The BU45K342G-TL specifically provides a fixed delay variant, distinguishing it from adjustable delay models. It serves as a legacy option for designs prioritizing simplicity and fixed timing characteristics over ultra-low current performance.

Replacement Considerations

The BD5234G-1 is listed as a similar specification replacement. Note that the substitute uses an SSOP-5 package instead of SSOP-3, requiring layout adjustments. The replacement offers adjustable delay and lower current consumption but may differ in output drive capabilities.