Texas Instruments TPA3123D2EVM

Overview

TPA3123D2EVM from Texas Instruments is a fully assembled, ready-to-use evaluation module for the TPA3123D2 25-W stereo Class-D audio power amplifier IC. It operates from 10 V to 30 V supply, delivers up to 24 W continuous output per channel into 4 Ω at 27 V with 10% THD+N, supports 3.2 Ω minimum load impedance, and features user-configurable gain (20–36 dB) via dual jumper-selectable inputs.

For engineers reviewing the TPA3123D2EVM datasheet, TPA3123D2EVM pinout, TPA3123D2EVM application, or TPA3123D2EVM equivalent, this module enables rapid functional validation of audio output stage design, gain calibration, shutdown/mute control behavior, and power-off de-pop circuit performance in stereo amplification systems.

Technical Context

The TPA3123D2EVM implements the full signal path of the TPA3123D2 IC-including analog input conditioning, internal Class-D modulation, gate drive, and LC filter output stages-using discrete 22 μH shielded inductors (L1/L2), 470 μF bulk electrolytic capacitors (C2/C8/C10/C17), and 0.1 μF ceramic bypass caps (C1/C7/C14). It integrates dedicated hardware for SHUTDOWN (active-low, TTL-compatible) and MUTE (active-high, TTL-compatible) control via momentary switches SW1/SW2.

A configurable power-off de-pop circuit-enabled by jumper J11-uses TLV431ACDBZR shunt regulator (D1), MMBT3904 transistor (Q4), and selectable resistors (R13 or R17) to suppress turn-off transients either by ramping down the BYPASS pin voltage or pulling SD low during VCC decay, depending on resistor selection.

Key Specifications

Availability

TPA3123D2EVM is available at Aetrix Electronics and suitable for audio system prototyping, Class-D amplifier validation, and embedded speaker driver qualification requiring stable component supply, traceable sourcing, and lifecycle continuity support.

Supply support for TPA3123D2EVM 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 company headquartered in Dallas, Texas, delivering analog, embedded processing, and connectivity solutions across industrial, automotive, and personal electronics markets.

The TPA3123D2EVM belongs to TI's Audio Amplifier Evaluation Module product line, designed specifically to accelerate development and verification of Class-D audio power stages using TI's integrated amplifier ICs in real-world PCB environments.

FAQ

What is the primary function of the TPA3123D2EVM?

The TPA3123D2EVM is an evaluation module built around the TPA3123D2 stereo Class-D audio power amplifier IC. Its primary function is to provide engineers with a fully assembled, test-ready platform to validate amplifier performance-including output power, THD+N, gain configuration, control interface behavior (SHUTDOWN/MUTE), and power-off de-pop functionality-without requiring custom PCB design or component sourcing. The TPA3123D2EVM includes all necessary passive components, filtering, and user-accessible jumpers/switches for immediate bench testing.

Does the TPA3123D2EVM support both single-ended and differential inputs?

No, the TPA3123D2EVM accepts standard single-ended analog audio inputs via RCA jacks (J9 for left, J10 for right), consistent with the TPA3123D2 IC's native input architecture. The TPA3123D2 IC itself does not support differential inputs; it uses single-ended LIN and RIN pins referenced to AGND. The TPA3123D2EVM schematic confirms direct connection of RCA sources to these pins through series resistors and coupling capacitors, with no differential input circuitry implemented on the board.

How is gain configured on the TPA3123D2EVM?

Gain on the TPA3123D2EVM is configured using two onboard jumpers: J1 (GAIN0) and J2 (GAIN1). Installing or removing each jumper sets the corresponding IC pin to GND or VCC, selecting one of four discrete gain settings: 20 dB (both jumpers installed), 26 dB (J1 installed, J2 removed), 32 dB (J1 removed, J2 installed), or 36 dB (both jumpers removed). This mapping matches Table 2 in the SLOU208 User's Guide and is implemented using TTL-compatible logic levels directly tied to the TPA3123D2PWP IC's GAIN0/GAIN1 pins.

Can the TPA3123D2EVM drive 8 Ω speakers effectively?

Yes, the TPA3123D2EVM can drive 8 Ω speakers, though output power will be reduced compared to 4 Ω operation. At VCC = 27 V, the TPA3123D2 IC delivers approximately 12 W per channel into 8 Ω (calculated from P = V²/(2×R) assuming rail-limited swing), well within its 3.2 Ω minimum load specification. The TPA3123D2EVM's LC output filters (22 μH + 10 μF) are optimized for stability across 3.2–8 Ω loads, and thermal performance remains acceptable due to lower dissipation at higher impedances. No hardware modification is required.

What safety precautions apply when operating the TPA3123D2EVM?

Per the SLOU208 User's Guide, the TPA3123D2EVM must operate strictly within 10 V–30 V input voltage range; exceeding this may cause irreversible damage. Output connections must stay within 0 V–30 V differential range. Several components-including power inductors, output MOSFETs, and bulk capacitors-reach case temperatures >85°C during normal operation; avoid contact and use non-conductive probes. Electrostatic discharge (ESD) precautions are mandatory due to the open-board construction. The TPA3123D2EVM is not FCC/CE/RoHS certified and is intended solely for engineering evaluation-not end-product deployment.