STMicroelectronics TDA7491P

Overview

TDA7491P from STMicroelectronics is a dual-channel BTL Class-D audio amplifier 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 four fixed gain settings (20/26/30/32 dB) via GAIN0/GAIN1 pins.

For engineers reviewing the TDA7491P datasheet, TDA7491P pinout, TDA7491P application, or TDA7491P equivalent, this page provides verified functional context, validated pin roles, confirmed thermal and electrical specs, and real-world use cases in compact display audio systems where heatsink-free operation and filterless design reduce BOM count.

Technical Context

The TDA7491P integrates two fully independent Class-D amplifier channels in a single PowerSSO-36 EPD package, each featuring differential inputs, unipolar PWM modulation, and internal oscillator (290–350 kHz). Its architecture eliminates external LC filters via optimized modulation and includes dedicated diagnostic (DIAG), synchronization (SYNCLK), and gain-setting logic.

It implements integrated protection including short-circuit detection, thermal shutdown at 150 °C, undervoltage lockout (4.5 V), and pop-free startup/shutdown sequencing. The exposed pad down (EPD) package enables direct PCB thermal coupling, eliminating discrete heatsinks while maintaining junction-to-case thermal resistance of 2 °C/W.

Key Specifications

Pinout & Package

Package: PowerSSO-36 with exposed pad down (EPD), thermally optimized for PCB ground-plane heatsinking. Exposed pad must be soldered to large copper area connected to PGND.

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 TDA7491P offers identical performance at lower cost for commercial temperature grade applications; versus TAS5142AIDBTR, it trades programmability for simpler hardware integration, lower power consumption, and reduced bill-of-materials.

Availability

TDA7491P is available at Aetrix Electronics and suitable for LCD television audio subsystems, computer monitor sound systems, digital signage players, and home theater-in-a-box (HTIB) designs requiring stable component supply, long-lifecycle support, and consistent thermal performance.

Supply support for TDA7491P 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, and microcontroller solutions for industrial, automotive, and consumer markets.

The TDA7491P belongs to ST's high-efficiency audio amplifier product line, engineered specifically for space-constrained, thermally sensitive display applications where filterless Class-D operation and integrated protection reduce system-level design risk.

FAQ

What is the minimum recommended PCB copper area for thermal management?

The PowerSSO-36 EPD package requires ≥400 mm² of 2-oz copper connected to the exposed pad and tied to PGND. ST's evaluation board uses a 20 mm × 20 mm thermal pad with 8 vias (0.3 mm diameter) to inner ground planes. Below this area, derating is necessary above 70 °C ambient.

Can the TDA7491P drive 4 Ω speakers reliably?

Yes - the datasheet confirms 12 W per channel into 4 Ω at 10 V supply with 10% THD. The 3 A overcurrent protection threshold and 0.2 Ω R_ds(on) ensure safe operation, but thermal limits require adequate PCB copper area and ambient ≤60 °C for sustained 4 Ω loads.

How does the DIAG pin indicate fault conditions?

DIAG is an open-drain output pulled low during thermal shutdown, output short-circuit, or undervoltage lockout. It remains high-impedance during normal operation. External pull-up to VDDS (3.3 V) is required; a 10 kΩ resistor suffices for microcontroller GPIO monitoring.

Is external LC filtering ever required with the TDA7491P?

No - the device is explicitly designed for filterless operation using spread-spectrum modulation. ST's reference design (Figure 47) shows direct speaker connection. LC filters may be added only for EMI compliance in specific regulatory environments, not for basic functionality.