STMicroelectronics STA350BWTR

Overview

STA350BWTR from STMicroelectronics is a 2.1-channel high-efficiency digital audio system-on-chip (Sound Terminal®) integrating FFX™ Class-D amplifier, 96 kHz DSP engine, I²C control interface, and configurable DRC/EQ processing. It delivers up to 2 × 18 W + 1 × 40 W into 2 × 4 Ω / 1 × 8 Ω in 2.1 mode at 25 V, supports 32–192 kHz I²S input, and embeds thermal/short-circuit protection. It targets compact home theater soundbars and automotive rear-seat entertainment systems requiring integrated audio processing and power output.

For engineers reviewing the STA350BWTR datasheet, STA350BWTR pinout, STA350BWTR application, or STA350BWTR equivalent, key selection considerations include its ternary PWM output architecture, dual-band DRC configuration capability, LFE-specific bass boost with 0.125 dB resolution, 8 user-programmable biquads per channel, and PowerSSO-36 EPD package thermal performance.

Technical Context

The STA350BWTR implements a fully digital audio signal path: I²S input feeds a 96 kHz internal processing core with programmable FIR/IIR filtering, dynamic range compression (dual-band B2DRC or independent limiters), and EQ-DRC using filtered signals. Its FFX™ modulation supports four hardware-configurable output modes-including stereo ternary PWM, 2.1-channel mixed binary/ternary, mono-BTL, and line-out + PWM-each with dedicated gain, mute, and protection logic.

Control is handled via I²C with selectable slave address; register mapping enables per-channel volume (±42 dB to −80 dB, 0.125 dB steps), soft-volume ramping, zero-detect/invalid-input muting, and fast EQ preset recall using three coefficient banks. Clock management includes selectable master clock ratio, AM interference switching, and noise-shaping topology selection for EMI reduction.

Key Specifications

Pinout & Package

STA350BWTR uses the PowerSSO-36 EPD (exposed pad down) package - a thermally enhanced 36-pin surface-mount housing with bottom-side thermal slug for direct PCB copper pour attachment. This configuration achieves 1.5 °C/W junction-to-board thermal resistance under standard JEDEC 2s2p layout, critical for sustained 2.1-channel output power delivery.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 2.1-channel digital audio system applications.

Compared with TAS5825M and STA339BW, the STA350BWTR uniquely balances LFE-targeted signal processing, ternary PWM efficiency, and thermal robustness in a single PowerSSO-36 EPD package-making it optimal for space-constrained 2.1 systems demanding both high bass output and low distortion.

Availability

STA350BWTR is available at Aetrix Electronics and suitable for home theater soundbars, automotive rear-seat entertainment modules, and smart speaker base units requiring stable component supply, long-term lifecycle support, and consistent thermal performance across production volumes.

Supply support for STA350BWTR 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, designing and manufacturing microcontrollers, analog ICs, power management devices, and audio processors for industrial, automotive, and consumer markets.

The STA350BWTR belongs to ST's Sound Terminal® family-engineered specifically for highly integrated, thermally efficient digital audio systems that replace multi-chip solutions with single-package processing, amplification, and protection.

FAQ

What is the maximum continuous output power per channel in 2.1 mode?

The STA350BWTR delivers 2 × 18 W into 4 Ω (left/right) and 1 × 40 W into 8 Ω (LFE) at 25 V supply with THD+N <1% at 1 kHz. These values are measured under JEDEC-standard PCB thermal conditions with 2s2p copper pour; actual output depends on heatsinking, ambient temperature, and duty cycle.

Does STA350BWTR support I²S input with 24-bit word length and 44.1 kHz sample rate?

Yes. The device accepts I²S data with 16-, 20-, or 24-bit word length and supports input sample rates from 32 kHz to 192 kHz-including 44.1 kHz and 48 kHz-via programmable interpolation ratio and master clock configuration registers (addresses 0x00–0x01).

How is thermal protection implemented, and can it be disabled?

Thermal protection triggers automatic shutdown when junction temperature exceeds 150 °C, with programmable warning threshold (125–145 °C) and recovery hysteresis. It cannot be fully disabled but may be bypassed via register 0x00 bit 6 (thermal warning recovery bypass), retaining hard shutdown at absolute max temperature.

Can the STA350BWTR operate with a 12 V supply in mono-BTL mode?

Yes. In mono-BTL mode, it delivers 1 × 45 W into 4 Ω at 12 V (per datasheet Table 6). Output scales linearly with supply voltage squared; full 90 W rating requires ≥24.5 V. Operation at 12 V remains within recommended conditions and activates all protections normally.