LM4700T Equivalent & Substitute Parts Reference

Part Overview

The LM4700T is a Class AB audio amplifier IC manufactured by Texas Instruments, designed for mono audio applications with 30W output power at 8Ω load impedance. The device is packaged in TO-220-11 form factor with integrated protection features including mute, short-circuit protection, and thermal management.

The LM4700T is classified as an obsolete product. Identification of equivalent and substitute parts is necessary for design continuity, procurement planning, and system maintenance where original components are no longer available through standard distribution channels.

Substiute Parts

LM4700T

Texas InstrumentsIn Stock: 1524LM4700T Datasheet

Current PartRFQ

LM2876TF/NOPB

Texas InstrumentsIn Stock: 3350LM2876TF/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM4700T is determined by the following critical parameters:

Mandatory Compatibility Criteria:

• Amplifier type: Class AB
• Channel configuration: 1-Channel (Mono)
• Package form factor: TO-220-11 or TO-220-11 Isolated
• Mounting method: Through Hole
• Operating temperature range: -20°C ~ 85°C minimum
• Protection features: Mute and Short-Circuit Protection required

Acceptable Variation Parameters:

• Maximum output power: Equal to or greater than 30W @ 8Ω
• Supply voltage range: Must encompass or match the operating range of 20V ~ 60V or ±10V ~ ±30V
• RoHS and REACH compliance status may differ

The LM2876TF/NOPB qualifies as a direct substitute based on matching all mandatory criteria while providing enhanced output power (40W vs. 30W) and improved compliance status.

Parameter Comparison

Engineering Selection Recommendations

The LM2876TF/NOPB is the manufacturer-recommended substitute for the obsolete LM4700T. Selection of this substitute is based on the following engineering factors:

Product Status Consideration: The LM4700T is classified as obsolete, whereas the LM2876TF/NOPB maintains active product status with confirmed inventory availability (3300 pieces in stock versus 1505 for the original part).

Compliance and Certification: The LM2876TF/NOPB achieves ROHS3 compliance, providing improved environmental and regulatory alignment compared to the non-compliant LM4700T. Both parts maintain REACH Unaffected and EAR99 ECCN classifications.

Electrical Performance: The LM2876TF/NOPB delivers 40W output power at 8Ω load, exceeding the 30W specification of the LM4700T. Supply voltage ranges are compatible within the operating envelope, with the substitute supporting 20V ~ 60V and ±10V ~ ±30V.

Package and Mechanical Compatibility: Both devices utilize TO-220-11 packaging with through-hole mounting. The LM2876TF/NOPB features an isolated tab variant, which provides thermal and electrical isolation benefits in applications requiring ground isolation.

Functional Feature Alignment: Core protection features (mute, short-circuit protection, thermal protection) are present in both devices. The LM4700T includes an additional standby feature not specified for the LM2876TF/NOPB; however, this does not preclude substitution in applications where standby functionality is not required.

Frequently Asked Questions (FAQ)

Q: Can the LM2876TF/NOPB directly replace the LM4700T in existing PCB designs?

A: Yes, the LM2876TF/NOPB is pin-compatible and functionally equivalent for mono Class AB amplifier applications. Both devices use the TO-220-11 package with through-hole mounting. The isolated tab variant of the LM2876TF/NOPB may require PCB layout verification if thermal isolation is critical to the original design.

Q: What is the difference between TO-220-11 and TO-220-11 Isolated Tab packaging?

A: The TO-220-11 Isolated Tab variant provides electrical and thermal isolation of the mounting tab from the device substrate. This is beneficial in applications requiring ground isolation or where the heat sink is connected to a different potential than the device ground. Standard TO-220-11 packages have the tab electrically connected to the substrate.

Q: Is the higher output power of the LM2876TF/NOPB (40W vs. 30W) a concern for compatibility?

A: No. Higher output power capability does not create compatibility issues. The LM2876TF/NOPB will operate within the same electrical and thermal parameters as the LM4700T when driving equivalent loads. The increased power rating provides design margin and improved performance headroom.

Q: What is the impact of the LM4700T's standby feature not being specified for the LM2876TF/NOPB?

A: The standby feature is an optional operational mode. If the original design does not utilize standby functionality, this difference is not relevant. If standby operation is required, alternative substitutes should be evaluated or the design should be modified to accommodate the absence of this feature in the LM2876TF/NOPB.

Q: Are there any supply voltage range limitations when substituting the LM2876TF/NOPB?

A: The LM2876TF/NOPB supports 20V ~ 60V and ±10V ~ ±30V supply ranges, which are slightly narrower than the LM4700T specification (20V ~ 64V, ±10V ~ ±32V). Designs operating at the upper limits of the original specification (64V or ±32V) must be verified to ensure operation within the substitute's rated range.

Q: Does the ROHS3 compliance of the LM2876TF/NOPB affect circuit performance?

A: No. RoHS compliance relates to material composition and environmental standards, not electrical performance. The LM2876TF/NOPB delivers equivalent electrical characteristics and protection features as the LM4700T.