STMicroelectronics TDA7491LP13TR

Overview

TDA7491LP13TR from STMicroelectronics is a dual-channel, 5 W + 5 W BTL Class-D audio amplifier IC designed for stereo audio output in LCD TVs and monitors. It operates from a single 5–14 V supply, delivers ≥90% efficiency at 5 W per channel into 8 Ω (V_CC = 9 V, THD = 10%), supports four fixed gain settings (20/26/30/32 dB), and features filterless operation with differential inputs.

For engineers reviewing the TDA7491LP13TR datasheet, TDA7491LP13TR pinout, TDA7491LP13TR application, or TDA7491LP13TR equivalent, key selection considerations include its PowerSSO-36 EPD thermal package, dual-channel BTL architecture, standby/mute control interface, diagnostic output (pin DIAG), and compatibility with 4 Ω and 8 Ω loads without external LC filters.

Technical Context

The TDA7491LP13TR integrates two identical Class-D amplifier channels with unipolar PWM modulation, internal 320 kHz oscillator (±30 kHz), and selectable master/slave clock synchronization via SYNCLK. Each channel uses differential analog inputs (INPA/INNA, INPB/INNB) and delivers complementary BTL outputs (OUTPA/OUTNA, OUTPB/OUTNB) directly to speakers.

It implements integrated protection including short-circuit detection (IOCP ≥ 3 A), thermal shutdown at 150 °C, undervoltage lockout (V_UVP = 4.5 V), and open-drain diagnostic reporting (pin DIAG). Gain is set by two digital inputs (GAIN0/GAIN1), and power-stage regulation provides separate 3.3 V supplies for signal (VDDS) and power stage (VDDPW).

Key Specifications

Pinout & Package

Package: PowerSSO-36 EPD (Exposed Pad Down), thermally enhanced surface-mount package with exposed ground pad for PCB heatsinking. Requires solder connection of EP pad to large copper pour for thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TDA7491P and TDA7491HV, the TDA7491LP13TR offers tape-and-reel delivery optimized for automated SMT assembly, while maintaining identical thermal and electrical performance - making it the preferred choice for high-volume LCD TV manufacturing.

Availability

TDA7491LP13TR is available at Aetrix Electronics and suitable for LCD television audio subsystems, monitor integrated speakers, and set-top box audio output requiring stable component supply, thermal reliability, and RoHS-compliant packaging.

Supply support for TDA7491LP13TR 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 TDA7491LP13TR belongs to ST's audio power amplifier product line, engineered specifically for energy-efficient, space-constrained visual display systems where thermal management and BOM simplification are critical design constraints.

FAQ

What is the minimum recommended PCB copper area for the exposed pad (EP) in PowerSSO-36 EPD?

The exposed pad must be soldered to a minimum 100 mm² copper pour connected to PGND, with ≥4 thermal vias (0.3 mm diameter) to inner ground planes. Per Section 5.9 and Figure 36 of the datasheet, this achieves R_{th j-amb} ≈ 24 °C/W and supports full 5 W/channel output without derating at 25 °C ambient.

Can the TDA7491LP13TR drive 3 Ω speakers?

No - the device is characterized and specified only for 4 Ω and 8 Ω loads. Driving 3 Ω increases current demand beyond the 3 A overcurrent threshold (Table 5), triggering IOCP protection and disabling output. ST does not guarantee safe operation below 4 Ω.

How is gain configured when GAIN0 and GAIN1 are left floating?

GAIN0 and GAIN1 have internal pull-down resistors (per Section 5.3 and Table 7), defaulting to logic low. This selects the 20 dB gain setting. For reliable operation, ST recommends actively driving both pins to defined logic levels rather than relying on internal pulls.

Does the TDA7491LP13TR require an external bootstrap capacitor?

No - the device uses a charge-pump-based high-side gate driver that self-generates the required floating voltage. No external bootstrap capacitor or diode is needed, simplifying layout and reducing component count compared to discrete half-bridge drivers.