STMicroelectronics TDA7493

Overview

TDA7493 from STMicroelectronics is a dual-channel BTL Class-D audio amplifier delivering 3.0 W + 3.0 W into 4 Ω loads at 5 V with filterless operation, THD = 10%, and 83% efficiency. It features four fixed gain settings (6/12/15.6/18 dB), differential inputs, and integrated thermal/short-circuit protection. Designed for compact LCD TV and monitor audio systems requiring low-EMI, single-supply operation.

For engineers reviewing the TDA7493 datasheet, TDA7493 pinout, TDA7493 application, or TDA7493 equivalent, this page provides verified technical context, HTSSOP24 package details, gain configuration logic, filterless modulation behavior, and real-world design constraints including EMI mitigation and clock synchronization requirements.

Technical Context

The TDA7493 implements unipolar PWM modulation per channel, generating differential outputs that swing between 0 and +V_CC or 0 and −V_CC, effectively doubling the audible-band noise rejection and enabling filterless operation up to 50 cm cable length. Its internal oscillator sets switching frequency at ~315 kHz (adjustable via ROSC pin), and SYNCLK supports master/slave synchronization across multiple devices.

Gain is digitally selected via GAIN0/GAIN1 pins using internal resistor networks (6/12/15.6/18 dB), with pull-down defaults ensuring 6 dB startup. Standby mode reduces quiescent current to 1 µA and includes pre-charge/mute sequencing to suppress speaker pop, while differential input structure provides ≥60 dB crosstalk and 60 kΩ input resistance.

Key Specifications

Pinout & Package

HTSSOP24 package with exposed pad down (EPD); thermal pad must be soldered to PCB ground plane for thermal performance and electrical reference. Pin count: 24 + exposed GND pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPA2013D1 and MAX9718, the TDA7493 uniquely combines filterless operation, differential inputs, programmable gain, and master/slave clocking-making it optimal for space-constrained, noise-prone LCD display audio where timing coherence and EMI control are mandatory.

Availability

TDA7493 is available at Aetrix Electronics and suitable for LCD monitor audio subsystems, USB-powered speaker cradles, and smart display docking stations requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for TDA7493 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, microcontrollers, and automotive ICs with strong emphasis on industrial and consumer system integration.

The TDA7493 belongs to ST's audio power amplifier product line, engineered specifically for cost-sensitive, space-constrained visual display systems requiring high-efficiency, low-EMI, and single-supply Class-D audio performance.

FAQ

What is the maximum recommended speaker cable length for filterless operation?

The TDA7493 datasheet specifies ≤50 cm for reliable filterless operation. Longer cables increase EMI radiation and risk audible artifacts due to parasitic inductance/capacitance interacting with the unipolar PWM waveform. For cables exceeding 50 cm, an LC low-pass filter (e.g., 15 µH + 0.22 µF per channel for 4 Ω) is required to meet EMC standards and preserve audio fidelity.

How does the TDA7493 handle thermal overload?

When junction temperature exceeds 150 °C, the TDA7493 enters thermal shutdown: all outputs go high-impedance, gain stages disable, and quiescent current drops to <1 µA. Recovery occurs automatically once T_j falls below 140 °C hysteresis threshold. The HTSSOP24 EPD package's 2 °C/W R_th(j–case) enables full 3 W/channel operation on standard PCBs without heatsinks under typical ambient conditions.

Can the TDA7493 be used with single-ended input sources?

Yes-single-ended inputs are supported via external resistive biasing (e.g., 39 kΩ to V_CC/2) per channel, as documented in Figure 12 of the datasheet. However, differential mode is preferred: it delivers 60 dB crosstalk and superior noise immunity. Single-ended use requires anti-pop circuitry (Figure 13) and forfeits common-mode rejection, increasing susceptibility to display-related switching noise.

What happens if the ROSC resistor value exceeds 60 kΩ?

ROSC > 60 kΩ forces the TDA7493 into error mode: internal oscillator fails to start, SYNCLK remains inactive, and amplifier outputs stay muted. The device draws ~7 mA quiescent current but produces no audio. To ensure reliable operation, ROSC must be ≤60 kΩ (e.g., 39 kΩ yields ~315 kHz switching frequency). In slave mode, ROSC is left floating to configure SYNCLK as input.