LM346M/NOPB Equivalent & Substitute Parts

Part Overview

The LM346M/NOPB is a general-purpose operational amplifier featuring four independent circuits in a 16-SOIC surface mount package, manufactured by Texas Instruments. This device is classified as obsolete, indicating discontinued production and limited availability in the market. The LM346M/NOPB was designed for applications requiring multiple amplification stages with moderate bandwidth and low input bias current characteristics. Due to its obsolete status, identifying functionally compatible substitute components is essential for design continuity, production planning, and long-term system reliability.

Substiute Parts

LM346M/NOPB

Texas InstrumentsIn Stock: 1050LM346M/NOPB Datasheet

Current PartRFQ

PGA280AIPW

Texas InstrumentsIn Stock: 1447PGA280AIPW Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM346M/NOPB requires evaluation of functional and physical compatibility based on the following critical parameters:

Functional Compatibility Criteria:

• Amplifier type classification and circuit configuration
• Number of independent amplification circuits
• Slew rate and gain bandwidth product performance
• Input bias current and input offset voltage specifications
• Output current capability per channel
• Supply voltage operating range

Physical Compatibility Criteria:

• Surface mount packaging technology
• Package footprint and pin count
• Moisture sensitivity level classification
• Regulatory compliance (RoHS3, REACH)

The substitute part PGA280AIPW is identified as a manufacturer-recommended alternative. However, this substitution involves functional trade-offs and design considerations that must be evaluated against specific application requirements. The PGA280AIPW operates as a programmable gain amplifier with differential output configuration, featuring a single circuit in a 24-TSSOP package, which differs fundamentally from the LM346M/NOPB's four-circuit general-purpose architecture.

Parameter Comparison

Engineering Selection Recommendations

Product Status Consideration: The LM346M/NOPB is classified as obsolete, while the PGA280AIPW maintains active production status. Active product status ensures continued availability, manufacturing support, and compliance with current regulatory standards. The PGA280AIPW is ROHS3 compliant and REACH unaffected, meeting modern environmental and regulatory requirements equivalent to the LM346M/NOPB.

Compliance and Certification: Both components are ROHS3 compliant and REACH unaffected, confirming compatibility with current environmental regulations. The PGA280AIPW operates across an extended temperature range (-40°C to 105°C) compared to the LM346M/NOPB (0°C to 70°C), providing broader operational flexibility for industrial and extended-temperature applications.

Functional Differences: The PGA280AIPW introduces significant functional differences that require circuit redesign consideration. The single-circuit configuration necessitates multiple devices for applications originally designed around the four-circuit LM346M/NOPB architecture. The programmable gain feature and differential output configuration represent enhanced functionality not present in the general-purpose LM346M/NOPB design.

Performance Trade-offs: The PGA280AIPW demonstrates superior performance in slew rate (2 V/µs versus 0.4 V/µs), gain bandwidth product (6 MHz versus 1.2 MHz), input bias current (0.8 pA versus 50 nA), and input offset voltage (50 µV versus 500 µV). These improvements support higher-frequency applications and reduced noise performance. However, the minimum supply voltage requirement increases from 3 V to 10 V, which may impact low-voltage system designs.

Package Consideration: The transition from 16-SOIC to 24-TSSOP packaging requires PCB layout modification and updated assembly procedures. The 24-TSSOP package provides improved thermal characteristics and pin density compared to the 16-SOIC format.

Frequently Asked Questions (FAQ)

Q: Can the PGA280AIPW directly replace the LM346M/NOPB in existing designs?

A: Direct pin-for-pin replacement is not possible. The PGA280AIPW features a different package (24-TSSOP versus 16-SOIC), different pin count, and different functional architecture (single programmable gain circuit versus four general-purpose circuits). Circuit redesign and PCB layout modification are required.

Q: What is the primary reason for substituting the LM346M/NOPB?

A: The LM346M/NOPB is classified as obsolete, indicating discontinued production. The PGA280AIPW is an active product with ongoing manufacturing support, ensuring long-term component availability and supply chain reliability.

Q: Are there supply voltage compatibility issues between these components?

A: Yes. The LM346M/NOPB operates with a minimum supply voltage of 3 V, while the PGA280AIPW requires a minimum of 10 V. Designs operating at supply voltages below 10 V cannot use the PGA280AIPW without additional voltage regulation or alternative component selection.

Q: How does the circuit count difference affect system design?

A: The LM346M/NOPB integrates four independent amplifier circuits in a single package, while the PGA280AIPW provides one circuit. Applications requiring multiple amplification stages must either use multiple PGA280AIPW devices or select alternative multi-circuit amplifier components.

Q: What are the moisture sensitivity implications?

A: The LM346M/NOPB has MSL 1 (unlimited shelf life), while the PGA280AIPW has MSL 2 (1-year shelf life). The PGA280AIPW requires more stringent moisture control during storage and handling, with reflow processing required within one year of package opening.

Q: Does the PGA280AIPW support the same output current capability?

A: The PGA280AIPW provides 15 mA output current per channel, compared to 20 mA for the LM346M/NOPB. Applications requiring maximum output current near 20 mA must verify that 15 mA output capability is sufficient for the intended load.

Q: What temperature range advantages does the PGA280AIPW offer?

A: The PGA280AIPW operates from -40°C to 105°C, compared to 0°C to 70°C for the LM346M/NOPB. This extended range supports industrial, automotive, and extended-temperature applications beyond the original LM346M/NOPB specification.