LM4906LD/NOPB Equivalent & Substitute Parts

Part Overview

The LM4906LD/NOPB is a Class AB mono audio amplifier IC manufactured by Texas Instruments, part of the Boomer® series. This device delivers 1W output power at 8Ω load in a 10-WSON (3x4) surface mount package. The LM4906LD/NOPB is classified as obsolete product status. Finding equivalent and substitute parts is necessary due to discontinued production and limited inventory availability. The LM4951SD/NOPB serves as the manufacturer-recommended substitute, offering enhanced specifications while maintaining core functional compatibility.

Substiute Parts

LM4906LD/NOPB

Texas InstrumentsIn Stock: 836LM4906LD/NOPB Datasheet

Current PartRFQ

LM4951SD/NOPB

Texas InstrumentsIn Stock: 35194LM4951SD/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM4906LD/NOPB is determined by the following critical parameters:

Functional Compatibility Criteria:

• Amplifier topology: Class AB mono configuration
• Channel configuration: Single-channel (mono) output
• Mounting technology: Surface mount
• Package family: 10-WSON variants
• Feature set: Depop, shutdown, and thermal protection functions
• Operating temperature range: -40°C ~ 85°C minimum

Electrical Compatibility Criteria:

• Supply voltage overlap within specified ranges
• Output power capability at standard load impedance (8Ω)
• Thermal and protection feature parity

The LM4951SD/NOPB qualifies as a direct substitute based on identical topology, channel configuration, feature set, and operating temperature range. Enhanced specifications (higher output power and extended supply voltage range) provide superior performance margins while maintaining backward compatibility in circuit applications designed for the LM4906LD/NOPB.

Parameter Comparison

Engineering Selection Recommendations

LM4951SD/NOPB Selection Basis:

The LM4951SD/NOPB is the manufacturer-recommended substitute for the obsolete LM4906LD/NOPB. Selection is justified on the following engineering grounds:

1. Product Status: The LM4951SD/NOPB maintains active product status with full manufacturing support, ensuring long-term availability and supply chain reliability compared to the obsolete LM4906LD/NOPB.

2. Compliance Certification: Both parts maintain ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements for new designs and production.

3. Functional Parity: Identical Class AB mono amplifier topology, feature set (depop, shutdown, thermal protection), and operating temperature range ensure functional equivalence in circuit applications.

4. Performance Enhancement: The LM4951SD/NOPB delivers 1.8W output power versus 1W, providing 80% additional power capability at identical 8Ω load impedance. Extended supply voltage range (2.7V ~ 9V) accommodates broader application requirements while remaining compatible with designs specified for 2.6V ~ 5.5V operation.

5. Package Consideration: The LM4951SD/NOPB uses a 10-WDFN (4x4) package versus the LM4906LD/NOPB 10-WFDFN (3x4) package. PCB layout modification is required; however, both packages are industry-standard 10-lead WSON variants with exposed pad thermal management.

Frequently Asked Questions (FAQ)

Q: Can the LM4951SD/NOPB directly replace the LM4906LD/NOPB without circuit modification?

A: Functional replacement is possible due to identical topology, channel configuration, and feature set. However, PCB layout modification is required because the LM4951SD/NOPB uses a 10-WDFN (4x4) package while the LM4906LD/NOPB uses a 10-WFDFN (3x4) package. Pin assignments are identical, but physical footprint dimensions differ. Verify PCB layout compatibility before implementation.

Q: What is the significance of the higher output power specification in the LM4951SD/NOPB?

A: The LM4951SD/NOPB delivers 1.8W at 8Ω load compared to 1W for the LM4906LD/NOPB. This 80% power increase provides design margin and improved audio performance in applications requiring higher output levels. Existing circuit designs specified for 1W operation remain fully compatible and benefit from enhanced performance headroom.

Q: Are there supply voltage compatibility concerns when substituting the LM4951SD/NOPB?

A: The LM4951SD/NOPB supply voltage range (2.7V ~ 9V) encompasses the LM4906LD/NOPB range (2.6V ~ 5.5V). The substitute operates across the original part's voltage specification with extended upper limit capability. Minimum voltage increases from 2.6V to 2.7V; verify that application power supplies meet this 2.7V minimum requirement.

Q: Why is the LM4906LD/NOPB classified as obsolete?

A: Obsolete status indicates discontinued production by Texas Instruments. The LM4951SD/NOPB represents the active replacement in the Boomer® amplifier series, offering enhanced specifications and guaranteed long-term availability.

Q: What compliance certifications apply to both parts?

A: Both the LM4906LD/NOPB and LM4951SD/NOPB maintain ROHS3 compliance and REACH unaffected status. Both are classified under ECCN EAR99 and HTSUS 8542.33.0001. Moisture sensitivity level is 1 (unlimited) for both devices.

Q: Are there thermal management differences between the two packages?

A: Both packages feature exposed pad thermal management in 10-lead WSON configuration. The LM4951SD/NOPB (4x4) provides slightly larger package dimensions compared to the LM4906LD/NOPB (3x4), potentially offering marginal thermal performance improvement. Consult thermal simulation and datasheet thermal resistance specifications for specific application requirements.