NJU6355EM Equivalent & Substitute Parts Reference

Part Overview

The NJU6355EM is a Real Time Clock (RTC) IC with integrated clock/calendar functionality manufactured by Nisshinbo Micro Devices Inc. This component operates as a 4-Wire Serial interface device in an 8-SOIC surface mount package. The NJU6355EM is classified as obsolete product status, necessitating identification of active equivalent alternatives for new designs and ongoing production requirements. Substitute parts must maintain functional compatibility through matching interface protocols, package dimensions, and electrical operating parameters.

Substiute Parts

NJU6355EM

Nisshinbo Micro Devices Inc.In Stock: 9907NJU6355EM Datasheet

Current PartRFQ

M41T00SM6F

STMicroelectronicsIn Stock: 26607M41T00SM6F Datasheet

SimilarRFQ

RX-4045NB:AAB PURE SN

EPSONIn Stock: 752RX-4045NB:AAB PURE SN Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the NJU6355EM are identified based on the following critical parameters that determine functional and physical compatibility:

Interface Protocol Compatibility: The NJU6355EM uses 4-Wire Serial interface. Substitute parts must support identical or compatible serial communication protocols to ensure direct replacement without firmware modification.

Package Compatibility: The 8-SOIC (0.154", 3.90mm Width) surface mount package defines the physical footprint. Substitute parts must use equivalent or compatible package dimensions to fit existing PCB layouts.

Electrical Operating Range: Supply voltage range (4.5V ~ 5.5V) and timekeeping current specifications establish the power budget constraints. Substitute parts must operate within or exceed these specifications.

Functional Features: Leap year support and time/date format specifications (HH:MM:SS 24-hour, YY-MM-DD-dd) are core functional requirements.

Compliance Standards: RoHS compliance and MSL rating ensure regulatory and manufacturing process compatibility.

The substitute parts identified below are grouped by their compatibility with these core parameters.

Parameter Comparison

Engineering Selection Recommendations

RX-4045NB:AAB PURE SN (EPSON) is the primary substitute for direct replacement of the NJU6355EM. This part maintains identical 4-Wire Serial interface protocol and compatible 8-SOIC package footprint. Both components support the same time/date format specifications and leap year functionality. The RX-4045NB:AAB PURE SN operates across an extended supply voltage range (1.7V ~ 5.5V) and demonstrates superior timekeeping current efficiency (1.2µA ~ 1.8µA) compared to the NJU6355EM. Operating temperature range extends to -40°C ~ 85°C, exceeding the original part specification. Product status is Active with ROHS3 compliance certification. This part is suitable for direct PCB layout replacement without design modification.

M41T00SM6F (STMicroelectronics) serves as a functional alternative when interface protocol modification is acceptable. This part uses I2C/2-Wire Serial interface instead of 4-Wire Serial, requiring firmware and circuit design changes. The M41T00SM6F maintains 8-SOIC package compatibility and identical time/date format support. Supply voltage range (2.7V ~ 5.5V) encompasses the NJU6355EM operating window. Product status is Active with ROHS3 compliance. This substitute requires design-level integration changes and is not suitable for direct pin-compatible replacement.

Selection between these substitutes depends on design constraints: RX-4045NB:AAB PURE SN for direct replacement; M41T00SM6F for designs where interface protocol modification is feasible.

Frequently Asked Questions (FAQ)

Q: Can the RX-4045NB:AAB PURE SN replace the NJU6355EM without PCB modification?

A: Yes. Both parts use 4-Wire Serial interface protocol and 8-SOIC package dimensions. Pin-to-pin compatibility and functional equivalence support direct substitution on existing PCB layouts.

Q: What is the primary difference between the RX-4045NB:AAB PURE SN and M41T00SM6F?

A: Interface protocol differs. RX-4045NB:AAB PURE SN uses 4-Wire Serial (matching NJU6355EM); M41T00SM6F uses I2C/2-Wire Serial. This requires firmware and circuit design changes for M41T00SM6F implementation.

Q: Does the RX-4045NB:AAB PURE SN package differ from the NJU6355EM?

A: Yes. RX-4045NB:AAB PURE SN uses 22-LFDFN package, while NJU6355EM uses 8-SOIC. Package difference requires PCB layout redesign and is not suitable for direct replacement in existing designs.

Q: Are both substitute parts RoHS compliant?

A: Yes. Both M41T00SM6F and RX-4045NB:AAB PURE SN carry ROHS3 compliance certification, meeting current regulatory requirements.

Q: What is the timekeeping current advantage of RX-4045NB:AAB PURE SN?

A: RX-4045NB:AAB PURE SN operates at 1.2µA ~ 1.8µA timekeeping current, compared to NJU6355EM at 4µA ~ 15µA. This represents significant power consumption reduction in battery-backed applications.

Q: Can M41T00SM6F operate at the NJU6355EM supply voltage range?

A: M41T00SM6F supply range (2.7V ~ 5.5V) encompasses the NJU6355EM range (4.5V ~ 5.5V). The substitute supports lower voltage operation, providing design flexibility.

Q: What inventory status applies to these substitute parts?

A: M41T00SM6F: 26,500 Pcs New Original In Stock. RX-4045NB:AAB PURE SN: 670 Pcs New Original In Stock. Both parts are actively stocked and available for procurement.