STMicroelectronics TDA7491P13TR

Overview

TDA7491P13TR from STMicroelectronics is a dual-channel BTL Class-D audio amplifier IC designed for LCD TV and monitor audio output stages. It delivers 10 W + 10 W continuous output into 6 Ω at 11 V supply with 10% THD, operates from a single 5–18 V rail, achieves 90% efficiency, and supports filterless operation without external LC output filters.

For engineers reviewing the TDA7491P13TR datasheet, TDA7491P13TR pinout, TDA7491P13TR application, or TDA7491P13TR equivalent, key selection considerations include its fixed-gain configuration (20/26/30/32 dB), differential input architecture for noise immunity, integrated standby/mute control, thermal overload and short-circuit protection, and PowerSSO-36 EPD package with exposed pad for direct PCB heatsinking.

Technical Context

The TDA7491P13TR integrates two identical BTL Class-D channels with unipolar PWM modulation, internal 320 kHz oscillator (250–400 kHz range), and configurable master/slave clock synchronization via SYNCLK. Each channel features independent differential inputs (INPA/INNA, INPB/INNB) and dual complementary PWM outputs (OUTPA/OUTNA, OUTPB/OUTNB).

It implements four fixed closed-loop gain settings via GAIN0/GAIN1 logic pins (18–34 dB typical), provides open-drain diagnostic output (DIAG) for fault reporting, and includes dedicated 3.3 V regulators for power stage (VDDPW) and signal blocks (VDDS), plus half-VDDS reference (VREF) for biasing.

Key Specifications

Pinout & Package

Package: PowerSSO-36 EPD (Exposed Pad Down), thermally enhanced surface-mount package with integrated ground-plane heatsink via exposed copper pad soldered to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel Class-D audio amplifier applications.

Compared with TDA7491LP, the TDA7491P13TR offers identical functionality at lower cost for standard consumer temperature range (-40 to 85 °C); versus TDA7492, it trades peak power for tighter THD performance at low-to-mid output levels and simpler gain configuration.

Availability

TDA7491P13TR is available at Aetrix Electronics and suitable for LCD TV audio subsystems, monitor integrated speakers, and set-top box audio output stages requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for TDA7491P13TR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in analog, power, microcontrollers, and automotive-grade ICs with strong focus on energy efficiency and system integration.

The TDA7491P13TR belongs to ST's TDA7xxx family of Class-D audio amplifiers, engineered specifically for cost-sensitive, space-constrained consumer display applications demanding high efficiency, low EMI, and robust protection.

FAQ

What is the recommended minimum PCB copper area for the exposed pad (EP) of the TDA7491P13TR?

The exposed pad must be connected to a solid ground plane with ≥400 mm² of 2-oz copper (minimum 200 mm² for basic thermal relief). ST recommends a 6 × 6 mm thermal pad with 9 vias (0.3 mm diameter) to inner ground layers to achieve R_{th j-amb} ≤ 24 °C/W. Insufficient copper area risks thermal shutdown under sustained 10 W/channel operation.

Can the TDA7491P13TR drive 4 Ω speakers, and what derating applies?

Yes - it supports 4 Ω loads with up to 12 W per channel at 10 V supply (THD = 10%). However, output power must be derated linearly above 10 V to maintain safe junction temperature: at 12 V, max output drops to 9 W/channel into 4 Ω. Thermal monitoring via DIAG pin is recommended for 4 Ω operation at elevated voltages.

How does the SYNCLK pin function in master vs. slave mode?

In master mode (SYNCLK left open), the internal 320 kHz oscillator drives both channels. In slave mode, an external clock (250–400 kHz) applied to SYNCLK synchronizes switching across multiple TDA7491P13TR devices to suppress beat frequencies and reduce EMI in multi-amplifier systems like soundbars. No external pull-up/down is required.

Is external LC filtering ever required with the TDA7491P13TR?

No - the device is certified for filterless operation into 4–8 Ω speakers per IEC 62368-1. External LC filters are optional only for EMI-sensitive environments (e.g., medical displays) or when driving long speaker cables (>1 m) that act as antennas. ST provides optimized LC values (e.g., 22 µH + 220 nF for 6 Ω) in the datasheet for such cases.