Texas Instruments LM4930LQBD

Overview

LM4930LQBD from Texas Instruments is an integrated audio subsystem combining stereo headphone and mono speaker amplifiers with 16-bit I²S DAC, 16-bit PCM voice codec, digital sidetone generation, and 32-step volume control. It delivers 25mW/channel into 32Ωheadphones and 330mW into 8Ωspeaker at AVDD = 3.0V, targeting mobile phone voice and audio playback functions.

For engineers reviewing the LM4930LQBD datasheet, LM4930LQBD pinout, LM4930LQBD application, or LM4930LQBD equivalent, key selection criteria include its dual-path (I²S + PCM) interface support, BTL mono speaker output, HP sense detection capability, and low-power shutdown current of 2μA - all critical for battery-constrained portable designs.

Technical Context

The LM4930LQBD integrates independent stereo DAC (48kHz) and voice-band codec (8kHz) paths sharing analog resources but operating concurrently. Its two-wire control interface configures mode-selectable signal routing (e.g., mono speaker only, stereo headphones only, or mixed voice+audio), gain settings, and sidetone attenuation via programmable registers.

It employs delta-sigma modulation with on-chip reference and bypass circuitry, eliminating external snubber networks or bootstrap capacitors. The device supports both 12.288MHz and 24.576MHz MCLK via CLOCK_DIV bit and features zero-crossing detection control (ZXD_DISABLE) to minimize click/pop during mode transitions.

Key Specifications

Pinout & Package

LM4930LQBD is packaged in a 44-lead WQFN (Package Number NJN0044A) with exposed thermal pad, optimized for compact mobile PCB layouts and thermal dissipation in space-constrained handheld devices.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar audio subsystem applications.

Compared with LM4930LQBD, LM49352RLX/NOPB offers higher speaker output and better supply rejection but increases package size and cost; TPA6138A2RTJR provides superior headphone performance but forfeits integrated voice functionality and system-level integration.

Availability

LM4930LQBD is available at Aetrix Electronics and suitable for mobile handset design, portable audio appliance development, and wearable voice interface projects requiring stable component supply across production lifecycles.

Supply support for LM4930LQBD includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with decades of expertise in low-power audio solutions for portable electronics.

The LM4930LQBD belongs to TI's Boomer™ audio power amplifier series, engineered specifically for space- and power-constrained mobile devices needing integrated voice + music playback in a single chip.

FAQ

What interfaces does the LM4930LQBD support for audio input?

The LM4930LQBD supports dual independent digital audio interfaces: a 16-bit I²S interface for full-range music playback (48kHz) and a 16-bit PCM interface for voice-band telephony (8kHz). Both operate concurrently, enabling simultaneous call and media playback. The I²S path connects to baseband or application processors for stereo content, while the PCM path handles narrowband voice streams and sidetone injection - all managed via the same two-wire control bus.

Does the LM4930LQBD require external passive components for headphone or speaker output?

No, the LM4930LQBD does not require external snubber networks or bootstrap capacitors for either headphone or speaker output stages. Its BTL mono speaker amplifier and single-ended headphone drivers are fully integrated with internal charge pumps and biasing. Only decoupling capacitors (e.g., 1µF BYPASS, 0.1µF DAC_REF) and optional external crystal (12.288/24.576MHz) are needed - significantly reducing BOM count and PCB footprint compared to discrete amplifier solutions.

How does the LM4930LQBD handle headphone insertion detection?

The LM4930LQBD implements hardware-based headphone detection using dedicated HPSENSE_IN and HPSENSE_OUT pins. When a 3-pole or 4-pole jack is inserted, it pulls HPSENSE_IN high, causing HPSENSE_OUT to assert logic high - signaling the host processor to switch audio routing from speaker to headphones. This detection operates independently of software control and is integrated into the device's mode configuration logic, enabling seamless plug-and-play operation without host-side ADC monitoring.

What is the maximum output power of the LM4930LQBD's mono speaker amplifier?

The LM4930LQBD's mono speaker amplifier delivers up to 330mW into an 8Ωload at AVDD = 3.0V with ≤1% THD+N at 1kHz. This specification is confirmed under standard test conditions (TA = 25°C, DVDD = 3.3V) and reflects typical performance in mobile handset speaker applications. Output scales with supply voltage: at AVDD = 5.0V, it achieves 1W into 8Ω- verified in the datasheet's KEY SPECIFICATIONS table under "PLS OUT at AVDD = 5.0V".

Can the LM4930LQBD operate with both 12.288MHz and 24.576MHz master clocks?

Yes, the LM4930LQBD supports both 12.288MHz and 24.576MHz master clock frequencies via the CLOCK_DIV bit in the VOICE/TEST CONFIG register. When CLOCK_DIV = 0, it expects 12.288MHz for standard 48kHz/8kHz sampling; when set to 1, it accepts 24.576MHz and internally divides by two. This flexibility allows compatibility with common crystal oscillators used in mobile platforms and simplifies clock tree design without requiring external frequency dividers.