STMicroelectronics TDA7718N

Overview

TDA7718N from STMicroelectronics is a 3-band car audio signal processor with integrated loudness, bass/middle/treble equalization, subwoofer low-pass filtering, and DC offset detection. It features 5 stereo input paths (quasi-differential, full-differential, or single-ended), 6-channel analog output (FL/FR/RL/RR/SWL/SWR), I²C digital control, and soft-step volume/speaker attenuation ranging from +23 dB to –79 dB in 1 dB steps - deployed in OEM automotive head units for real-time tonal shaping and amplifier protection.

For engineers reviewing the TDA7718N datasheet, TDA7718N pinout, TDA7718N application, or TDA7718N equivalent, key selection criteria include its TSSOP28 package compatibility, programmable 2nd-order filter center frequencies (e.g., bass at 60–200 Hz, treble at 10–17.5 kHz), SoftMute timing options (0.48–16 ms), and DC offset fault detection capability for power amplifier diagnostics.

Technical Context

The TDA7718N implements a fully configurable analog audio signal path controlled via I²C, with independent 2nd-order biquad filters for bass, middle, and treble bands - each offering programmable center frequency, Q factor, and ±15 dB gain/attenuation in 1 dB steps. Its input multiplexer supports simultaneous routing of up to five stereo sources, including one quasi-differential (QD1), one full-differential (FD1), and three single-ended (SE1–SE3) pairs.

Signal integrity is maintained through 95 dB input separation, 100 kΩ input impedance across all analog inputs, A-weighted output noise of 12 µV (typ.), and 98 dB SNR. The device integrates a dedicated DC offset detector with four sensitivity thresholds (±10 to ±130 mV) and programmable spike rejection (2–70 µs), enabling real-time diagnosis of downstream amplifier failures.

Key Specifications

Pinout & Package

TDA7718N is housed in a thermally enhanced TSSOP28 package (4.4 mm × 9.7 mm, 0.65 mm pitch), optimized for compact automotive PCB layouts and capable of dissipating up to 114 °C/W junction-to-ambient thermal resistance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar car audio processor applications.

Compared with TDA7719, the TDA7718N offers broader analog input flexibility and mature diagnostic features but lacks extended treble response; versus STA559BW, it provides superior analog signal conditioning and fault isolation capabilities essential for modular amplifier architectures.

Availability

TDA7718N is available at Aetrix Electronics and suitable for automotive infotainment systems, OEM head unit replacements, and in-vehicle diagnostic modules requiring stable component supply, long-lifecycle support, and AEC-Q100-aligned performance under temperature cycling and vibration stress.

Supply support for TDA7718N 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 automotive, industrial, and power management ICs with broad manufacturing scale and automotive qualification expertise.

The TDA7718N belongs to ST's TDA audio processor family, designed specifically for cost-sensitive yet feature-rich car radio platforms requiring high-fidelity analog signal conditioning, programmable EQ, and built-in amplifier diagnostics.

FAQ

What is the maximum number of stereo input sources supported by the TDA7718N?

The TDA7718N supports up to five stereo input sources: one quasi-differential (QD1), one full-differential (FD1), and three single-ended (SE1–SE3). The FD1 pins can alternatively be configured as two additional single-ended inputs (SE4 and SE5), enabling flexible source routing without external multiplexers.

Does the TDA7718N require external passive components for filter operation?

No external capacitors or resistors are required for its internal 2nd-order bass/middle/treble filters - all coefficients are digitally programmed via I²C. However, a 100 nF capacitor is recommended on the CREF pin (Pin 14) to stabilize the internal reference voltage for consistent filter response across temperature.

How does the DC offset detection circuit interface with external amplifiers?

The WIN_IN pin (Pin 28) connects directly to the output of an external power amplifier; the internal comparator monitors for rail imbalance. When offset exceeds the selected threshold (±10 to ±130 mV), DC_ERR (Pin 27) pulls low, signaling fault condition to the host MCU - enabling immediate mute or diagnostic logging without interrupting audio path.

Can the TDA7718N operate from a 5 V supply?

No - the TDA7718N requires a minimum 7.5 V supply and operates up to 10 V. It is designed for direct connection to automotive battery rails (nominal 12 V, derated to 8.5 V typical). Using 5 V will prevent proper biasing of analog stages and cause functional failure.