LM4121IM5-1.2 Equivalent & Substitute Parts

Part Overview

The LM4121IM5-1.2 is a Series Voltage Reference IC from Texas Instruments, designed to provide a fixed 1.25V output with ±0.5% tolerance. This component is classified as a Power Management (PMIC) device and is packaged in SOT-23-5 surface mount configuration. The part is currently marked as Obsolete, making identification of equivalent and substitute components essential for ongoing design support and production continuity.

Substiute Parts

LM4121IM5-1.2

Texas InstrumentsIn Stock: 1858LM4121IM5-1.2 Datasheet

Current PartRFQ

LM4121IM5-1.2/NOPB

Texas InstrumentsIn Stock: 4742LM4121IM5-1.2/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM4121IM5-1.2 is determined by strict equivalence across the following critical parameters:

• Fixed output voltage of 1.25V
• Output current capability of 5 mA
• Tolerance specification of ±0.5%
• Temperature coefficient of 50ppm/°C
• Input voltage range of 1.5V ~ 12V
• Supply current of 275µA
• Operating temperature range of -40°C ~ 85°C
• SOT-23-5 surface mount package configuration

The identified substitute part maintains identical electrical specifications and mechanical compatibility, differing only in packaging format and product lifecycle status.

Parameter Comparison

Engineering Selection Recommendations

The LM4121IM5-1.2/NOPB is a direct parametric equivalent to the LM4121IM5-1.2. Both parts are manufactured by Texas Instruments and maintain identical electrical and mechanical specifications across all critical parameters.

The primary distinction between these parts is product lifecycle status and regulatory compliance. The LM4121IM5-1.2 is marked as Obsolete, while the LM4121IM5-1.2/NOPB carries a Last Time Buy status, indicating extended availability. Additionally, the LM4121IM5-1.2/NOPB achieves ROHS3 compliance, whereas the original part is RoHS non-compliant.

For new designs or production continuity, the LM4121IM5-1.2/NOPB is the appropriate selection. The packaging format difference (Tape & Reel versus bulk) does not affect electrical performance and accommodates automated assembly processes.

Frequently Asked Questions (FAQ)

Q: Can LM4121IM5-1.2/NOPB be used as a direct replacement for LM4121IM5-1.2?

A: Yes. Both parts are parametrically identical across all electrical specifications, including output voltage, tolerance, temperature coefficient, noise characteristics, and operating ranges. The SOT-23-5 package configuration is identical, enabling direct board-level substitution.

Q: What does the "/NOPB" suffix indicate?

A: The "/NOPB" designation indicates the part is supplied in Tape & Reel (TR) packaging format without lead (Pb), reflecting RoHS3 compliance. The electrical performance remains unchanged from the base part number.

Q: Why is the original LM4121IM5-1.2 marked as Obsolete?

A: Obsolete status indicates the part has reached end-of-life and is no longer in active production. The LM4121IM5-1.2/NOPB provides continued availability with equivalent functionality and improved regulatory compliance.

Q: Are there differences in thermal performance between these parts?

A: No. Both parts maintain identical temperature coefficient specifications of 50ppm/°C and operate across the same temperature range of -40°C to 85°C (TA).

Q: Does packaging format affect circuit performance?

A: No. Tape & Reel and bulk packaging formats do not affect electrical performance. The difference is operational, relating to handling, storage, and automated assembly compatibility.