LP3985IM5X-5.0 Equivalent & Substitute Parts

Part Overview

The LP3985IM5X-5.0 is a linear voltage regulator IC from Texas Instruments designed for positive fixed 5V output at 150mA in a SOT-23-5 surface mount package. This part is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement. The device provides regulated 5V output with integrated protection features including over-current, over-temperature, and short-circuit protection, suitable for low-power applications requiring stable voltage regulation.

Substiute Parts

LP3985IM5X-5.0

Texas InstrumentsIn Stock: 22180LP3985IM5X-5.0 Datasheet

Current PartRFQ

LP3985IM5X-5.0/NOPB

Texas InstrumentsIn Stock: 2395LP3985IM5X-5.0/NOPB Datasheet

DirectRFQ

LP3985IM5-5.0/NOPB

Texas InstrumentsIn Stock: 8940LP3985IM5-5.0/NOPB Datasheet

Parametric EquivalentRFQ

MAX8878EUK50+

Analog Devices Inc./Maxim IntegratedIn Stock: 1058MAX8878EUK50+ Datasheet

MFR RecommendedRFQ

MAX8878EUK50+T

Analog Devices Inc./Maxim IntegratedIn Stock: 4797MAX8878EUK50+T Datasheet

MFR RecommendedRFQ

TC2185-5.0VCTTR

Microchip TechnologyIn Stock: 9142TC2185-5.0VCTTR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LP3985IM5X-5.0 is determined by the following critical parameters: fixed 5V output voltage, 150mA output current capability, SOT-23-5 package compatibility, positive output configuration, and surface mount mounting type. All substitute parts listed maintain these core electrical and mechanical specifications.

The substitute parts are grouped into three categories:

Direct Manufacturer Equivalents (Texas Instruments): LP3985IM5X-5.0/NOPB and LP3985IM5-5.0/NOPB are parametric equivalents from the same manufacturer with identical electrical specifications and packaging.

Manufacturer Recommended Alternatives (Analog Devices/Maxim): MAX8878EUK50+ and MAX8878EUK50+T provide equivalent functionality with identical output voltage and current ratings, though with minor variations in dropout voltage and quiescent current specifications.

Manufacturer Recommended Alternative (Microchip): TC2185-5.0VCTTR delivers equivalent 5V/150mA regulation with comparable performance characteristics.

All substitutes maintain the required SOT-23-5 package format, surface mount configuration, and core protection features (over-current, over-temperature, short-circuit).

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: LP3985IM5X-5.0/NOPB or LP3985IM5-5.0/NOPB are the preferred substitutes. Both are active products from Texas Instruments with identical electrical specifications to the obsolete LP3985IM5X-5.0, ROHS3 compliance, and superior inventory availability (2350 and 8842 units respectively). These parts require no design modifications and provide direct functional replacement.

Secondary Recommendation: TC2185-5.0VCTTR from Microchip Technology is suitable for applications where lower quiescent current (80 µA vs. 150 µA) is beneficial. This part maintains the same operating temperature range (-40°C ~ 125°C) as the original and offers ROHS3 compliance with strong inventory (9076 units).

Alternative Recommendation: MAX8878EUK50+T from Analog Devices/Maxim Integrated is compatible for designs tolerating a reduced operating temperature maximum of 85°C (versus 125°C). This part features higher maximum input voltage (6.5V) and includes reverse polarity protection. Inventory is adequate (4705 units). The tape and reel packaging (MAX8878EUK50+T) is preferred over cut tape (MAX8878EUK50+) for production environments.

All substitute parts maintain SOT-23-5 package compatibility, eliminating PCB layout modifications. Selection should prioritize active product status, ROHS3 compliance, and operating temperature requirements specific to the application.

Frequently Asked Questions (FAQ)

Q: Can LP3985IM5-5.0/NOPB replace LP3985IM5X-5.0 without design changes?

A: Yes. Both parts share identical electrical specifications (5V output, 150mA current, 0.1V dropout at 150mA, 150 µA quiescent current) and SOT-23-5 packaging. The primary difference is product status: LP3985IM5-5.0/NOPB is active while the original is obsolete. No PCB or schematic modifications are required.

Q: What is the difference between MAX8878EUK50+ and MAX8878EUK50+T?

A: Both parts are electrically identical with 5V output and 150mA current capability. The difference is packaging: MAX8878EUK50+ is supplied in cut tape format, while MAX8878EUK50+T is supplied in tape and reel format. For production assembly, tape and reel (MAX8878EUK50+T) is the standard choice.

Q: Why does TC2185-5.0VCTTR have lower quiescent current?

A: The TC2185-5.0VCTTR from Microchip Technology is designed with lower quiescent current (80 µA) compared to the LP3985 series (150 µA). This is a design characteristic of the Microchip device and can reduce standby power consumption in battery-powered applications. All other critical parameters remain equivalent.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All active substitute parts listed (LP3985IM5X-5.0/NOPB, LP3985IM5-5.0/NOPB, MAX8878EUK50+, MAX8878EUK50+T, and TC2185-5.0VCTTR) are ROHS3 compliant. The original LP3985IM5X-5.0 is non-compliant, making the substitutes necessary for RoHS-regulated applications.

Q: What is the maximum operating temperature difference between substitutes?

A: The LP3985 series and TC2185-5.0VCTTR operate to 125°C maximum, while the MAX8878 series operates to 85°C maximum. For applications requiring full -40°C to 125°C operation, use LP3985IM5X-5.0/NOPB, LP3985IM5-5.0/NOPB, or TC2185-5.0VCTTR.

Q: Can these parts be used interchangeably on the same PCB?

A: Yes. All substitute parts use the SOT-23-5 package with identical pin configuration and spacing. No PCB layout modifications are required for substitution. Verify that your application's operating temperature and input voltage requirements align with the selected part's specifications.