STMicroelectronics TDA7491MV

Overview

TDA7491MV from STMicroelectronics is a mono BTL Class-D audio amplifier IC designed for LCD TV and monitor audio output stages. It delivers 25 W continuous power into 6 Ω at 16 V supply with 10% THD, operates from 5–18 V single supply, achieves 90% efficiency, and supports filterless operation without external LC output filtering.

For engineers reviewing the TDA7491MV datasheet, TDA7491MV pinout, TDA7491MV application, or TDA7491MV equivalent, key selection considerations include its differential input architecture, four fixed gain settings (20/26/30/32 dB), integrated standby/mute control, thermal overload and short-circuit protection, and PowerSSO-36 EPD package with exposed pad down for passive heatsinking.

Technical Context

The TDA7491MV implements a self-oscillating PWM modulator with internal 310 kHz switching frequency (adjustable via ROSC pin) and supports both master (internal oscillator) and slave (external clock synchronization via SYNCLK) modes. Its differential analog inputs reject common-mode noise, while the BTL output stage drives speakers directly without output coupling capacitors.

It integrates dual 3.3 V regulators (VDDPW for power stage, VDDS for signal blocks), diagnostic open-drain output (DIAG) for fault reporting, and programmable gain via GAIN0/GAIN1 pins. Protection features include overvoltage (19–21 V), undervoltage lockout (<4 V), overcurrent (5 A threshold), and thermal shutdown at 150 °C junction temperature.

Key Specifications

Pinout & Package

Package: PowerSSO-36 with exposed pad down (EPD), thermally enhanced for direct PCB copper area heat dissipation; no external heatsink required.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TDA7491P, the TDA7491MV offers superior thermal handling and higher output power in the same footprint; versus TPA3110D2, it trades voltage headroom for integration simplicity and lower system-level component count.

Availability

TDA7491MV is available at Aetrix Electronics and suitable for LCD TV manufacturing, monitor audio subsystems, and set-top box audio output stages requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for TDA7491MV 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, specializing in analog, power, microcontrollers, and automotive ICs with strong emphasis on energy efficiency and industrial reliability.

The TDA7491MV belongs to ST's high-efficiency Class-D audio amplifier product line, engineered specifically for space- and thermal-constrained consumer display applications where filterless operation and integrated protection are essential.

FAQ

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

The datasheet specifies a 9 cm² copper area with thermal vias under the exposed pad for optimal thermal performance. With this layout, the device sustains 25 W output at 85 °C ambient without additional heatsinking. Reducing copper area below 6 cm² requires derating output power per Figure 27's derating curves.

How does the DIAG pin indicate fault conditions?

DIAG is an open-drain output that pulls low during thermal shutdown, overcurrent, overvoltage, or undervoltage events. Its state is latched until power cycle or STBY pin toggling. The pin remains high during normal operation and mute mode, enabling simple microcontroller GPIO monitoring without additional circuitry.

Can the TDA7491MV drive 4 Ω loads reliably?

Yes - the device supports 4 Ω loads with appropriate derating: maximum continuous output is 18 W at 16 V, 10% THD. The internal overcurrent protection triggers at 5 A, and thermal shutdown activates at 150 °C junction temperature, ensuring safe operation even under sustained 4 Ω loading with adequate PCB copper.

Is external clock synchronization mandatory for multi-device audio systems?

No - synchronization via SYNCLK is optional. When unused, the device operates in master mode using its internal ROSC-set oscillator. However, synchronizing multiple TDA7491MV units (e.g., left/right channels) eliminates beat frequencies and reduces EMI in tightly packed layouts, especially in dual-amplifier monitor designs.