LM4845ITL/NOPB Equivalent & Substitute Parts

Part Overview

The LM4845ITL/NOPB is a Class AB audio amplifier IC manufactured by Texas Instruments, designed for mono audio applications with stereo headphone output capability. This device is classified as Obsolete, making identification of functionally equivalent substitute parts essential for ongoing design support and component procurement.

The LM4845ITL/NOPB delivers 1.15W output power at 8Ohm load and operates across a 2.7V to 5.5V supply voltage range. Its integration of I2C control, mute, shutdown, and thermal protection features positions it within the Boomer® audio amplifier series. Due to its obsolete status, sourcing equivalent active alternatives is necessary for new production runs and design continuity.

Substiute Parts

LM4845ITL/NOPB

Texas InstrumentsIn Stock: 1182LM4845ITL/NOPB Datasheet

Current PartRFQ

LM49101TM/NOPB

National SemiconductorIn Stock: 1773LM49101TM/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM4845ITL/NOPB is determined by the following critical parameters:

Electrical Compatibility Criteria:

• Class AB amplifier topology
• 1-Channel (Mono) with Stereo Headphones output configuration
• Supply voltage range: 2.7V ~ 5.5V
• Operating temperature range: -40°C ~ 85°C (TA)
• Output power capability at standard loads (8Ohm and 32Ohm)

Mechanical Compatibility Criteria:

• Surface Mount mounting type
• 25-WFBGA package footprint compatibility

Functional Feature Alignment:

• I2C control interface
• Thermal protection
• Shutdown capability
• Volume control functionality

The LM49101TM/NOPB qualifies as a manufacturer-recommended substitute based on matching these core parameters while maintaining functional equivalence within the Boomer® audio amplifier family.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: LM49101TM/NOPB

The LM49101TM/NOPB is the manufacturer-recommended substitute for the obsolete LM4845ITL/NOPB. Selection of this substitute is based on the following engineering factors:

Product Status Alignment: The LM49101TM/NOPB maintains Active product status, ensuring long-term availability and manufacturing support compared to the Obsolete LM4845ITL/NOPB. This directly addresses supply chain continuity requirements.

Electrical Parameter Equivalence: Both devices operate within identical supply voltage ranges (2.7V ~ 5.5V) and temperature specifications (-40°C ~ 85°C TA). The Class AB topology and mono-with-stereo-headphones output configuration are preserved, maintaining functional compatibility with existing circuit designs.

Mechanical Compatibility: Both parts utilize Surface Mount technology with 25-WFBGA package footprints, enabling direct PCB layout compatibility without redesign.

Feature Parity: Core control features including I2C interface, thermal protection, shutdown capability, and volume control are present in both devices, supporting equivalent system-level functionality.

Output Power Consideration: The LM49101TM/NOPB delivers 1.3W at 8Ohm load, exceeding the LM4845ITL/NOPB specification of 1.15W. At 32Ohm load, the substitute provides 45mW versus the original 75mW. Applications operating at 8Ohm loads benefit from increased headroom; designs dependent on 32Ohm performance require load impedance verification.

Compliance Status: RoHS3 compliance is confirmed for the LM4845ITL/NOPB. Verification of RoHS compliance status for the LM49101TM/NOPB is recommended for applications subject to regulatory requirements.

Frequently Asked Questions (FAQ)

Q: Can the LM49101TM/NOPB be used as a direct replacement for the LM4845ITL/NOPB?

A: Yes, the LM49101TM/NOPB is the manufacturer-recommended substitute. Both devices share identical package footprints (25-WFBGA), supply voltage ranges (2.7V ~ 5.5V), operating temperature specifications (-40°C ~ 85°C TA), and core functional features (I2C control, thermal protection, shutdown, volume control). No PCB layout modifications are required for substitution.

Q: What are the output power differences between these devices?

A: At 8Ohm load, the LM49101TM/NOPB provides 1.3W compared to the LM4845ITL/NOPB at 1.15W. At 32Ohm load, the LM4845ITL/NOPB delivers 75mW while the LM49101TM/NOPB delivers 45mW. Applications operating at 8Ohm loads experience improved performance; designs relying on 32Ohm performance require load impedance confirmation.

Q: Why is the LM4845ITL/NOPB classified as Obsolete?

A: The LM4845ITL/NOPB has reached end-of-life status and is no longer in active production. The LM49101TM/NOPB, maintained in Active status, represents the current equivalent solution within the Boomer® audio amplifier product line.

Q: Are there any feature differences between the two devices?

A: The LM4845ITL/NOPB includes SPI and Mute features in addition to I2C control. The LM49101TM/NOPB features Differential Inputs and Depop functionality. Both devices include I2C, thermal protection, shutdown, and volume control. Application-specific requirements for SPI, Mute, Differential Inputs, or Depop functionality should be evaluated against circuit design needs.

Q: Is the 25-WFBGA package identical between both devices?

A: Yes, both the LM4845ITL/NOPB and LM49101TM/NOPB utilize the 25-WFBGA package with identical footprints. PCB layout compatibility is maintained without modification.

Q: What is the supply voltage compatibility?

A: Both devices operate across the identical supply voltage range of 2.7V to 5.5V. Existing power supply designs require no modification for substitution.

Q: Should RoHS compliance be verified before substitution?

A: The LM4845ITL/NOPB is confirmed ROHS3 Compliant. RoHS compliance status for the LM49101TM/NOPB should be verified through the manufacturer datasheet if the application is subject to RoHS regulatory requirements.