LM3674MF-1.5 Equivalent & Substitute Parts

Part Overview

The LM3674MF-1.5 is a buck switching regulator IC from Texas Instruments, delivering a fixed 1.5V output at 600mA with input voltage range of 2.7V to 5.5V. This part is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production requirements. The device operates at 2MHz switching frequency with integrated synchronous rectification in a compact SC-74A (SOT-23-5) surface mount package.

Substiute Parts

LM3674MF-1.5

Texas InstrumentsIn Stock: 1158LM3674MF-1.5 Datasheet

Current PartRFQ

LM3674MF-1.5/NOPB

Texas InstrumentsIn Stock: 1128LM3674MF-1.5/NOPB Datasheet

DirectRFQ

ADP2108AUJZ-1.5-R7

Analog Devices Inc.In Stock: 3539ADP2108AUJZ-1.5-R7 Datasheet

MFR RecommendedRFQ

MCP1603T-150I/OS

Microchip TechnologyIn Stock: 1136MCP1603T-150I/OS Datasheet

MFR RecommendedRFQ

RT8009-15GJ5

Richtek USA Inc.In Stock: 1074RT8009-15GJ5 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM3674MF-1.5 is determined by the following critical parameters:

• Fixed output voltage of 1.5V
• Output current capability of 600mA or greater
• Input voltage range compatibility (minimum 2.7V, maximum 5.5V)
• Buck topology with synchronous rectification
• Surface mount package (SOT-23-5 or equivalent form factor)
• Single output configuration

Substitute parts must maintain these core electrical specifications to ensure functional equivalence in the target application. Package compatibility includes both standard SOT-23-5 and thin-profile TSOT-23-5 variants, as both fit the same PCB footprint with identical pin assignments.

Parameter Comparison

Engineering Selection Recommendations

Direct Replacement (Highest Compatibility): LM3674MF-1.5/NOPB is the direct equivalent from Texas Instruments. It maintains identical electrical specifications and package format while offering active product status and RoHS3 compliance. This part is the preferred choice for designs requiring no circuit modifications.

Manufacturer-Recommended Alternatives: ADP2108AUJZ-1.5-R7 (Analog Devices) and RT8009-15GJ5 (Richtek) are manufacturer-recommended substitutes meeting all core electrical requirements. Both are active products with RoHS3 compliance. The ADP2108AUJZ-1.5-R7 offers extended operating temperature range (-40°C to 125°C) and lower minimum input voltage (2.3V). The RT8009-15GJ5 maintains the original operating temperature ceiling at 85°C.

Current-Limited Alternative: MCP1603T-150I/OS (Microchip Technology) provides functional substitution with a reduced output current rating of 500mA versus the original 600mA specification. This part is suitable only for applications where the load current does not exceed 500mA. It offers extended operating temperature range and active product status with RoHS3 compliance.

All substitute parts are active products with current manufacturing support and RoHS3 compliance, eliminating obsolescence risk and meeting modern regulatory requirements.

Frequently Asked Questions (FAQ)

Q: Can LM3674MF-1.5/NOPB be used as a direct drop-in replacement? A: Yes. LM3674MF-1.5/NOPB is electrically and mechanically identical to LM3674MF-1.5, with identical pin configuration, package footprint, and electrical specifications. No circuit modifications are required.

Q: What is the difference between SOT-23-5 and TSOT-23-5 packages? A: TSOT-23-5 is a thin-profile variant of SOT-23-5 with the same pin configuration and PCB footprint. Both packages are mechanically compatible on standard PCB layouts. The primary difference is reduced package height, which may be relevant for space-constrained applications.

Q: Is MCP1603T-150I/OS suitable for all applications using the LM3674MF-1.5? A: MCP1603T-150I/OS is suitable only for applications where the maximum load current does not exceed 500mA. The original LM3674MF-1.5 supports 600mA output current. Verify your application's current requirements before selecting this part.

Q: Why is the ADP2108AUJZ-1.5-R7 recommended despite different switching frequency? A: The ADP2108AUJZ-1.5-R7 operates at 3MHz versus the original 2MHz, but maintains identical output voltage, current capability, and input voltage range. The higher switching frequency may reduce output filter component size in some designs. Both frequencies are standard for buck regulator applications and do not affect functional compatibility.

Q: Are all substitute parts RoHS3 compliant? A: Yes. All substitute parts listed are RoHS3 compliant. The original LM3674MF-1.5 is RoHS non-compliant. If RoHS compliance is required for your application, use LM3674MF-1.5/NOPB or any of the manufacturer-recommended alternatives.

Q: What is the minimum input voltage difference between parts? A: The ADP2108AUJZ-1.5-R7 accepts input voltage as low as 2.3V, while the original LM3674MF-1.5 requires minimum 2.7V. The RT8009-15GJ5 operates at 2.5V minimum. Verify your power supply voltage to ensure compatibility with the selected part.