LP2951ACN Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The LP2951ACN is a linear voltage regulator IC from Texas Instruments designed for positive adjustable (fixed) output applications. This device delivers 100mA output current in an 8-DIP through-hole package and includes integrated protection features for over-current, over-temperature, and short-circuit conditions. The LP2951ACN is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. Direct manufacturer alternatives and parametric equivalents are available from Texas Instruments with improved compliance status.

Substiute Parts

LP2951ACN

Texas InstrumentsIn Stock: 5640LP2951ACN Datasheet

Current PartRFQ

LP2951ACN/NOPB

Texas InstrumentsIn Stock: 949LP2951ACN/NOPB Datasheet

DirectRFQ

LP2951CN/NOPB

Texas InstrumentsIn Stock: 5458LP2951CN/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LP2951ACN is determined by strict equivalence across the following critical parameters:

Electrical Parameters (Must Match):

• Output configuration: Positive
• Output type: Adjustable (Fixed)
• Number of regulators: 1
• Voltage - Input (Max): 30V
• Voltage - Output (Min/Fixed): 1.235V (5V)
• Voltage - Output (Max): 29V
• Current - Output: 100mA
• Voltage Dropout (Max): 0.6V @ 100mA
• Current - Quiescent (Iq): 120 µA
• Current - Supply (Max): 14 mA
• Control Features: Enable
• Protection Features: Over Current, Over Temperature, Short Circuit
• Operating Temperature: -40°C ~ 125°C (TJ)

Mechanical Parameters (Must Match):

• Mounting Type: Through Hole
• Package / Case: 8-DIP (0.300", 7.62mm)
• Supplier Device Package: 8-PDIP

Substitute Parts Identified:

1. LP2951ACN/NOPB – Direct manufacturer equivalent with active product status and improved RoHS3 compliance
2. LP2951CN/NOPB – Parametric equivalent with active product status and improved RoHS3 compliance

Both substitute parts maintain identical electrical and mechanical specifications to the main part number, ensuring functional interchangeability in circuit applications.

Parameter Comparison

Engineering Selection Recommendations

For New Designs and Production Continuity:

The LP2951ACN is classified as obsolete. Both substitute parts—LP2951ACN/NOPB and LP2951CN/NOPB—are active products from Texas Instruments and provide identical electrical and mechanical performance.

Compliance Advantage:

Both substitute parts carry ROHS3 compliance certification, whereas the original LP2951ACN is RoHS non-compliant. This compliance improvement is significant for applications subject to environmental regulations and procurement standards requiring RoHS adherence.

Inventory and Availability:

• LP2951ACN: 5600 Pcs (obsolete status)
• LP2951ACN/NOPB: 885 Pcs (active)
• LP2951CN/NOPB: 5400 Pcs (active)

Selection Criteria:

For new designs and ongoing production, select either LP2951ACN/NOPB or LP2951CN/NOPB based on availability and supply chain requirements. Both parts are functionally equivalent and mechanically interchangeable. The /NOPB designation indicates lead-free solder ball compatibility, aligning with modern manufacturing processes.

Frequently Asked Questions (FAQ)

Q: Can LP2951ACN/NOPB and LP2951CN/NOPB be used interchangeably with LP2951ACN?

A: Yes. All three part numbers share identical electrical specifications (output voltage range, current rating, dropout voltage, protection features) and mechanical packaging (8-DIP through-hole). Direct substitution is supported without circuit modification.

Q: What is the difference between LP2951ACN/NOPB and LP2951CN/NOPB?

A: Both parts are parametric equivalents with identical electrical and mechanical characteristics. The primary difference is product status: both are active. Selection between them should be based on inventory availability and supply chain logistics.

Q: Why is the original LP2951ACN marked as obsolete?

A: The LP2951ACN is obsolete due to its RoHS non-compliant status. Texas Instruments has transitioned to active production of RoHS3-compliant variants (LP2951ACN/NOPB and LP2951CN/NOPB) to meet current regulatory and customer requirements.

Q: Are there any thermal or performance differences between the substitute parts?

A: No. All three parts operate across the same temperature range (-40°C ~ 125°C TJ) and deliver identical quiescent current (120 µA), supply current (14 mA), and dropout voltage (0.6V @ 100mA) specifications.

Q: What does the /NOPB suffix indicate?

A: The /NOPB designation indicates lead-free solder ball packaging, compliant with RoHS directives and modern surface-mount assembly processes.

Q: Can these parts be used in legacy designs originally specified with LP2951ACN?

A: Yes. The substitute parts maintain full backward compatibility. No circuit redesign or PCB modification is required. Direct pin-for-pin replacement is supported.

Q: What is the MSL (Moisture Sensitivity Level) rating?

A: All three parts carry MSL 1 (Unlimited), indicating no moisture sensitivity restrictions during storage or handling.