REG101NA-2.5/3K Equivalent & Substitute Parts

Part Overview

The REG101NA-2.5/3K is a linear voltage regulator IC from Texas Instruments designed for positive fixed 2.5V output at 100mA in SOT-23-5 surface mount packaging. This device operates across -40°C to 85°C and features integrated over-current and over-temperature protection with enable control functionality. The part is classified as Last Time Buy, indicating end-of-life status. Identifying equivalent and substitute parts is necessary to ensure design continuity, maintain supply chain flexibility, and support long-term product availability for applications requiring 2.5V regulation at moderate current levels.

Substiute Parts

REG101NA-2.5/3K

Texas InstrumentsIn Stock: 2670REG101NA-2.5/3K Datasheet

Current PartRFQ

LP2985-25DBVR

Texas InstrumentsIn Stock: 25512LP2985-25DBVR Datasheet

MFR RecommendedRFQ

REG101NA-2.5/250

Texas InstrumentsIn Stock: 1509REG101NA-2.5/250 Datasheet

Parametric EquivalentRFQ

MIC5219-2.5YM5-TR

Microchip TechnologyIn Stock: 4459MIC5219-2.5YM5-TR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the REG101NA-2.5/3K is determined by the following critical parameters: fixed output voltage of 2.5V, SOT-23-5 package compatibility, positive output configuration, enable control feature, and surface mount mounting type. Parts are grouped into two categories based on substitution relationship:

Parametric Equivalent: REG101NA-2.5/250 shares identical electrical specifications and performance characteristics with the main part, differing only in tape reel quantity designation.

Manufacturer Recommended Substitutes: LP2985-25DBVR and MIC5219-2.5YM5-TR provide functional equivalence with enhanced specifications. These parts maintain the 2.5V fixed output, SOT-23-5 package, enable control, and over-current/over-temperature protection. Substitution is valid where the enhanced current capacity, improved quiescent current performance, or extended operating temperature range do not create design conflicts.

Parameter Comparison

Engineering Selection Recommendations

REG101NA-2.5/250: This parametric equivalent is suitable for direct replacement where inventory of the REG101NA-2.5/3K becomes unavailable. Electrical performance and thermal characteristics are identical. Selection is appropriate for applications with existing REG101NA-2.5/3K designs requiring continuation. Both parts carry Last Time Buy status, indicating limited future availability.

LP2985-25DBVR: This Texas Instruments part is recommended for new designs or redesigns where extended operating temperature range (-40°C to 125°C) is required. The Active product status ensures long-term availability. Enhanced current capacity (150mA) and improved quiescent current (95 µA) provide design margin. Higher maximum input voltage (16V) accommodates broader input supply ranges. Short circuit protection adds robustness. ROHS3 compliance and REACH unaffected status match the original part.

MIC5219-2.5YM5-TR: This Microchip Technology part offers the highest current capacity (500mA) and lowest quiescent current (8 µA), making it suitable for power-sensitive or higher-load applications. Active product status guarantees availability. Extended operating temperature range and reverse polarity protection enhance system reliability. ROHS3 compliance and REACH unaffected status are maintained. Cross-manufacturer substitution requires validation of control pin compatibility and PCB layout considerations.

Frequently Asked Questions (FAQ)

Q: Can REG101NA-2.5/250 be used as a direct replacement for REG101NA-2.5/3K?

A: Yes. REG101NA-2.5/250 is a parametric equivalent with identical electrical specifications, output voltage, current rating, dropout voltage, quiescent current, and PSRR. The designation difference reflects tape reel quantity only. No circuit modifications are required.

Q: What are the key differences between LP2985-25DBVR and the original REG101NA-2.5/3K?

A: LP2985-25DBVR maintains the 2.5V output and SOT-23-5 package but offers higher output current (150mA vs 100mA), lower quiescent current (95 µA vs 500 µA), extended operating temperature range (-40°C to 125°C vs -40°C to 85°C), higher maximum input voltage (16V vs 10V), and additional short circuit protection. PSRR is lower at 45dB (1kHz) compared to 65dB (120Hz).

Q: Is MIC5219-2.5YM5-TR compatible with designs using REG101NA-2.5/3K?

A: MIC5219-2.5YM5-TR is functionally compatible in SOT-23-5 package and maintains 2.5V fixed output with enable control. However, it is a different manufacturer (Microchip vs Texas Instruments). Verification of control pin functionality, enable logic levels, and PCB layout is required before implementation. The significantly higher current capacity (500mA) and lower quiescent current (8 µA) may require circuit validation to ensure no unintended performance changes.

Q: Why does LP2985-25DBVR have higher dropout voltage than REG101NA-2.5/3K?

A: Dropout voltage is load-dependent. LP2985-25DBVR is specified at 150mA output current (0.58V), while REG101NA-2.5/3K is specified at 100mA (0.13V). At equivalent load currents, dropout characteristics differ due to internal circuit design differences between the two regulators.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. REG101NA-2.5/3K, REG101NA-2.5/250, LP2985-25DBVR, and MIC5219-2.5YM5-TR are all ROHS3 compliant with MSL 1 (Unlimited) moisture sensitivity level and REACH unaffected status.

Q: Which substitute part should be selected for new designs?

A: LP2985-25DBVR is recommended for new designs due to Active product status, ensuring long-term availability and supply continuity. Extended operating temperature range and enhanced protection features support broader application requirements.