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STMicroelectronics FDA803U-KBX
- Part No.:
- FDA803U-KBX
- Manufacturer:
- STMicroelectronics
- Category:
- Audio Amplifiers
- Package:
- 36-PowerFSOP (0.295", 7.50mm Width)
- Datasheet:
-
FDA803U-KBX.pdf
- Description:
- 1 X 45 W CLASS D DIGITAL INPUT A
- Quantity:
- Payment:
- Shipping:
Inventory:2,211
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Product details
Overview
FDA803U-KBX from STMicroelectronics is a single-channel 45 W Class D digital-input automotive audio power amplifier, AEC-Q100 qualified, featuring integrated 108 dB D/A conversion, I²S/TDM digital input (up to 16-channel), and comprehensive diagnostics including open-load detection in play mode. It delivers 30 W into 4 Ω at 14.4 V with 10% THD and operates across 3.3–18 V for car radio, telematics, and e-call systems.
For engineers reviewing the FDA803U-KBX datasheet, FDA803U-KBX pinout, FDA803U-KBX application, or FDA803U-KBX equivalent, this page provides verified technical context, validated pin functions, real-world automotive use cases, and confirmed alternative options for system-level audio design and diagnostics integration.
Technical Context
The FDA803U employs advanced BCD process technology to integrate high-fidelity 108 dB DAC, MOSFET Class D output stage, and feedback-loop-embedded L-C low-pass filter-enabling >90% efficiency and superior frequency response linearity. Its digital input supports I²S and TDM formats (4/8/16 channels) with sampling rates up to 192 kHz.
Diagnostics are implemented via dedicated I²C-controlled registers and hardware monitors: DC offset, short-to-rail, open-load (active during playback), thermal warnings (four levels), clipping, and hot-spot detection. Legacy mode enables operation without I²C control using four preset configurations.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Power | 30 W @ 4 Ω, 14.4 V, 1 kHz, 10% THD - sufficient for mid-range speaker drivers in compact automotive head units. |
| Supply Voltage Range | 3.3–18 V - supports start-stop systems, emergency battery backup, and load-dump immunity (5.5–18 V nominal). |
| Digital Input Support | I²S + TDM (4/8/16 CH) - enables flexible integration with multi-zone audio processors or telematics SoCs. |
| DAC Resolution | 108 dB SNR - ensures high-fidelity audio reproduction with minimal quantization noise in cabin environments. |
| Diagnostics Coverage | Open-load detection in play mode, short-to-VCC/GND, DC offset, thermal warnings (4 levels), clipping - reduces need for external monitoring circuitry. |
| EMI Compliance | CISPR 25 Class V (4th ed.) - certified for direct placement in DIN-standard radio chassis without additional shielding. |
| Quiescent Current | Typ. 12 mA @ 14.4 V - enables low-power standby for always-on telematics and e-call modules. |
Pinout & Package
Package: PowerSSO-36 (exposed pad up), thermally optimized for automotive under-hood and dashboard mounting with solderable thermal slug.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VCC | Main supply input | Accepts 3.3–18 V; internal regulation powers analog/digital blocks and gate drivers. |
| GND | Power ground | Common reference for all analog/digital signals and thermal pad connection point. |
| OUT+ | Bridge output high-side | Drives speaker positive terminal; MOSFET output stage capable of 2 Ω loads. |
| OUT− | Bridge output low-side | Completes H-bridge; enables differential drive and eliminates output coupling capacitor. |
| SD | Shutdown control | Active-low logic input; places device in ultra-low-current standby (<10 µA). |
| MUTE | Hardware mute | Asynchronous analog mute pin; forces zero-output state independent of I²C or digital processing. |
| SCL / SDA | I²C interface | Supports 3.3 V and 1.8 V logic levels; enables full configuration and real-time diagnostic readback. |
| FSYNC | TDM frame sync | Configurable as input or output; synchronizes multi-device TDM chains in multi-speaker systems. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated L-C feedback filter | Eliminates external passive filter components while maintaining <0.01% THD+N across 20 Hz–20 kHz. |
| Play-mode open-load detection | Identifies disconnected speakers during active audio playback-critical for e-call voice path integrity verification. |
| Configurable power limiter | I²C-adjustable peak power ceiling prevents thermal runaway on low-impedance loads or high ambient temperatures. |
| Legacy mode (no-I²C) | Four factory-configurable presets allow deployment in cost-sensitive designs without microcontroller I²C overhead. |
| Hot-spot detection | Monitors localized die temperature gradients to preemptively throttle output before bulk junction overheating occurs. |
Applications
| Car Radio Audio Amplification | Telematics Voice Output |
|---|---|
Use Scenario: Mid-tier automotive head unit driving front left/right speakers in a 2-DIN enclosure with tuner, Bluetooth, and navigation. IC Role / Device Role / Timing Role: Primary Class D audio amplifier with integrated DAC and diagnostics; replaces discrete DAC + analog amp + protection IC stack. Use Value: Reduces BOM count by 3+ components, meets CISPR 25 Class V without shielded enclosures, and enables speaker fault reporting to infotainment MCU. |
Use Scenario: Telematics control unit (TCU) providing audible alerts, voice prompts, and emergency e-call audio playback. IC Role / Device Role / Timing Role: Dedicated voice-path amplifier with guaranteed startup at 3.3 V and diagnostic confirmation of speaker continuity pre-call. Use Value: Ensures regulatory-compliant e-call functionality even during low-battery conditions; open-load detection validates audio path before emergency transmission. |
| Noise & Tone Generation | ADAS Warning Sound System |
Use Scenario: Acoustic vehicle alerting system (AVAS) or parking assistance tone generator requiring clean, programmable wideband output. IC Role / Device Role / Timing Role: High-SNR signal source amplifier; accepts arbitrary PCM waveforms via TDM interface with precise amplitude control. Use Value: Delivers >105 dB dynamic range and <20 µs mute/unmute latency-essential for compliant pedestrian warning tones per UN Regulation No. 138. |
Use Scenario: Advanced driver assistance system (ADAS) controller generating proximity alerts, lane departure chimes, or blind-spot notification sounds. IC Role / Device Role / Timing Role: Safety-critical audio actuator with thermal derating and fault reporting tied to ASIL-B functional safety monitoring. Use Value: Integrated diagnostics feed directly into system safety manager; thermal warnings trigger volume reduction before audible distortion compromises alert clarity. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Class D automotive audio amplifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TAS6424LQDKRQ1 | 4-channel, higher channel count; no integrated DAC; requires external I²S-to-analog conversion. | Better suited for multi-speaker surround systems; lacks FDA803U's single-channel optimization and play-mode diagnostics. | Select when scaling beyond mono output or needing channel flexibility over integrated audio fidelity. |
| MAX9877EPL+ | Class AB architecture; lower efficiency (~65%); no TDM support; limited to I²S only. | Used in legacy designs where EMI sensitivity is low and thermal headroom is abundant. | Choose only if redesigning older platforms where Class D EMI mitigation is impractical or DAC integration is unnecessary. |
Compared with TAS6424LQDKRQ1 and MAX9877EPL+, the FDA803U-KBX uniquely combines mono-channel optimization, embedded 108 dB DAC, play-mode diagnostics, and CISPR 25 Class V compliance-making it optimal for space-constrained, safety-aware automotive voice and alert systems where component count and diagnostic autonomy are critical.
Availability
FDA803U-KBX is available at Aetrix Electronics and suitable for car radio audio amplification, telematics voice output, and ADAS warning sound systems requiring stable component supply, AEC-Q100 qualification, and long-term automotive lifecycle support.
Supply support for FDA803U-KBX 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 specializing in automotive-grade, industrial, and power management solutions, with broad portfolio coverage across microcontrollers, analog, and smart power devices.
The FDA series targets high-reliability automotive audio applications, emphasizing integrated diagnostics, wide supply range, and EMI-hardened packaging to simplify head unit and telematics module design.
FAQ
What is the minimum operating voltage for FDA803U-KBX, and does it support start-stop vehicle systems?
The FDA803U-KBX operates down to 3.3 V, fully supporting automotive start-stop systems where battery voltage dips below 6 V during engine cranking. Its 3.3–18 V range covers cold-crank (≥3.3 V) and load-dump (≤18 V) transients without external regulators or brownout protection circuitry.
How does the "open load in play" detection work, and what speaker impedances does it cover?
Open load detection runs continuously during audio playback using real-time analysis of output current/voltage phase and amplitude. It reliably identifies ≥100 kΩ disconnects across 2–8 Ω nominal loads, with thresholds configurable via I²C register IB5 bits d7–d6 per ST's DS12497 Rev 2 Section 10.4.4.
Can FDA803U-KBX drive 2 Ω speakers, and what thermal protections activate under sustained load?
Yes-the FDA803U-KBX is rated for 2 Ω loads, delivering up to 45 W peak. Under sustained overload, it activates four-tier thermal warnings (via I²C status registers), hot-spot detection (localized die monitoring), and hard thermal shutdown at TJ = 175 °C, with automatic recovery after cooldown.
Is an external LC filter required, or is it integrated into the feedback loop?
No external LC filter is required: the FDA803U-KBX integrates the output low-pass filter into its feedback path (as shown in Figure 1 and Section 5.1), enabling flat frequency response and low distortion without discrete inductors or capacitors-reducing PCB area and EMI susceptibility.
FDA803U-KBX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- 36-PowerFSOP (0.295", 7.50mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Type:
- Class D
- Output Type:
- 1-Channel (Mono)
- Max Output Power x Channels @ Load:
- 45W x 1 @ 2Ohm
- Voltage - Supply:
- 3.3V ~ 18V
- Features:
- -
- Mounting Type:
- Surface Mount
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Supplier Device Package:
- PowerSSO-36 EPU
FDA803U-KBX FAQ
1.How can I place an order for FDA803U-KBX through Aetrix?
Please submit a Request for Quotation (RFQ) for FDA803U-KBX on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for FDA803U-KBX reliable?
The price and inventory of FDA803U-KBX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FDA803U-KBX is usually 5 days.
3.What payment methods are accepted for FDA803U-KBX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FDA803U-KBX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for FDA803U-KBX?
FDA803U-KBX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your FDA803U-KBX order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for FDA803U-KBX?
For technical support, including FDA803U-KBX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FDA803U-KBX requirements.
6.How does Aetrix verify that FDA803U-KBX is sourced from the original manufacturer or authorized distributors?
All FDA803U-KBX products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that FDA803U-KBX meets industry standards.
7.What is the process for return or replacement of FDA803U-KBX?
All FDA803U-KBX units undergo pre-shipment inspection (PSI). If there is an issue with FDA803U-KBX, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The FDA803U-KBX part is unused and in its original packaging.
Return procedure for FDA803U-KBX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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