STMicroelectronics TDA7439

Overview

TDA7439 from STMicroelectronics is a digitally controlled, three-band audio processor IC for car-radio and Hi-Fi systems, integrating stereo input multiplexing (4 inputs), independent left/right speaker attenuation (1-dB steps), treble/mid/bass tone control (±14 dB in 2-dB steps), volume control (−47 to 0 dB in 1-dB steps), and I²C serial interface. It uses bipolar/CMOS technology to achieve 0.01% THD, 106 dB SNR, and 90 dB channel separation.

For engineers reviewing the TDA7439 datasheet, TDA7439 pinout, TDA7439 application, or TDA7439 equivalent, key selection considerations include its SDIP30 package, 9 V supply operation, 2-dB tone resolution, dual mute capability (input stage + speaker), and programmable input gain (0–30 dB) for source-level adaptation in multi-source automotive head units.

Technical Context

The TDA7439 implements analog signal conditioning via resistor-switch networks and operational amplifiers, with tone stages configured using external passive components - bass/mid-range use T-type band-pass topologies (center frequency set by RB = 44 kΩ / RM = 25 kΩ plus external R/C), while treble uses a high-pass filter with fixed 25 kΩ internal resistor and external capacitor. All functions are controlled via a standard two-wire I²C bus (address 0x88) with auto-increment support.

Its architecture separates signal path stages: input multiplexer → gain stage → volume/tone/balance processing → speaker attenuators → stereo output. Power-on reset defaults to IN2 input, 28 dB gain, mute, and flat tone response. DC step error is limited to ≤3 mV between adjacent volume steps, ensuring silent channel transitions.

Key Specifications

Pinout & Package

Package: SDIP30 (30-pin shrink dual in-line plastic package, 0.400" width, ECOPACK® lead-free).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TDA7313 and CS4272-CZZ, the TDA7439 uniquely delivers integrated 3-band analog tone control in SDIP30 with zero external active components, making it optimal for analog-centric automotive and Hi-Fi designs where simplicity, low EMI, and proven reliability are prioritized over digital flexibility.

Availability

TDA7439 is available at Aetrix Electronics and suitable for automotive infotainment systems, aftermarket car stereos, and high-fidelity pre-amplifiers requiring stable component supply across extended production lifecycles.

Supply support for TDA7439 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 automotive, industrial, and power management ICs with broad analog and mixed-signal portfolio coverage.

The TDA7439 belongs to ST's legacy automotive audio processor family, designed specifically for cost-effective, high-SNR analog signal conditioning in resource-constrained car-radio platforms prior to widespread digital audio adoption.

FAQ

What is the recommended value for the CREF capacitor?

The datasheet specifies 10 µF as the nominal CREF value for stable biasing and proper power-on behavior. A 4.7 µF capacitor may be used if faster power-up is required, though this reduces the time constant governing internal reference settling and may affect initial mute timing consistency.

Does the TDA7439 support hardware volume control without I²C?

No - all functions including volume, tone, input selection, and speaker attenuation are exclusively controlled via the I²C serial interface. There are no analog control pins or potentiometer wiper connections; the device lacks any parallel or analog programming mode.

Can the TDA7439 drive headphones directly?

No - its LOUT/ROUT outputs are line-level (2.1–2.6 Vrms clipping, 10–70 Ω output impedance) and intended for connection to power amplifier inputs. Driving headphones would require additional buffering and current gain stages not provided internally.

Is the SDIP30 package RoHS-compliant?

Yes - the TDA7439 is supplied in an ECOPACK®-certified SDIP30 package with lead-free second-level interconnect, compliant with JEDEC Standard JESD97 and meeting RoHS Directive 2011/65/EU requirements.