STA51813TR - 40V 3.5A Quad Half-Bridge | STMicroelectronics
MPN: STA51813TR ✓ ActiveSTA51813TR Overview
A quad half-bridge is a power-conversion output topology commonly used in Class D audio systems. Each half-bridge switches a supply rail with controlled PWM signals, while an output filter reconstructs the amplified audio waveform. The STA51813TR is positioned as the final power stage of a stereo all-digital high-efficiency amplifier, where its multiple half-bridges support efficient power delivery and flexible channel configuration.
Key electrical characteristics include a 40 V maximum supply rating, 3.5 A power-stage current capability, and a complementary DMOS output stage with 200 mΩ RDS(on) as stated in the device description. The part includes thermal protection, thermal warning output, undervoltage protection, and short-circuit protection. These protections address common output-stage failure conditions involving excessive temperature, supply undervoltage, and overload or short circuits.
The STA51813TR uses Multipower BCD technology, combining analog power-processing functions with control logic in a monolithic structure. The device can operate as four single-ended channels, as two full bridges, or as a single bridge when CONFIG is tied to VDD. This flexibility makes it relevant to multi-channel audio systems, compact Class D power stages, and designs requiring different output configurations from the same package.
Typical applications include stereo all-digital high-efficiency amplifiers, multi-channel home-audio systems, powered speakers, soundbars, and other consumer audio products. The exposed thermal slug in the PowerSSO-36 package provides a direct thermal path from the IC to the PCB or heatsink, making thermal layout and copper-area management essential to reliable operation.
For PCB design, place the input, PWM, supply, ground, and output connections according to the manufacturer pin description table, and provide adequate low-impedance power and ground paths. Use the exposed pad as both a thermal path and, where the package construction requires it, a low-impedance electrical connection. Check the worst-case output power, thermal dissipation, and switching-node layout against the manufacturer application guidance.
This page organizes the electrical ratings, configuration options, protections, packaging details, and drop-in replacement guidance for engineers evaluating STA51813TR. It also highlights practical thermal and layout considerations that are essential when moving from a datasheet schematic to a working Class D audio power stage.
Drop-in alternatives for STA51813TR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
No drop-in alternatives available for this product.
Request AlternativesSTA51813TR Maximum Ratings & Electrical Characteristics
| Device Type | Quad power half-bridge digital audio amplifier output stage |
| Maximum Supply Voltage | 40 V |
| Power Stage Current Capability | 3.5 A |
| Output Configuration | 4 half-bridges, 2 full bridges, or 1 single bridge |
| Process Technology | Multipower BCD |
| Output Stage | Complementary DMOS |
| Output Transistor RDS(on) | 200 mΩ |
| Maximum Output Power | 24 W x 4 channels at THD = 10% |
| Thermal Protection | Yes |
| Thermal Warning Output | Yes |
| Undervoltage Protection | Yes |
| Short-Circuit Protection | Yes |
| Logic Input Compatibility | CMOS compatible |
| Package | PowerSSO-36 with exposed bottom pad |
| Package Type | 36-pin PowerSSO, surface mount |
| Mounting Type | Surface mount |
| CONFIG Configuration | Tie CONFIG to VDD for single-bridge operation with double current capability |
STA51813TR 36-pin powersso, surface mount Pin Configuration Guide
Pin configuration for STA51813TR (36-pin powersso, surface mount package). This analog component features input, output, and power supply pins. Refer to the manufacturer datasheet for offset null, compensation, and enable pin configurations. Ideal for signal conditioning and amplifier circuits.
No detailed pinout data available for STA51813TR.
Refer to the datasheet for full pin configuration.
Typical Applications
STA51813TR is suitable for 6 applications: Stereo All-Digital High-Efficiency Amplifier, Multi-Channel Home Audio Amplifier, Powered Speaker Output Stage, Soundbar Multi-Channel Amplification, Digital Speaker Amplifier Platform, Compact Class D Audio Power Module.
Stereo All-Digital High-Efficiency Amplifier
The STA51813TR fits the final output stage of a stereo all-digital high-efficiency amplifier because it integrates four power half-bridges, each capable of 3.5 A operation within the stated 40 V device rating. The manufacturer identifies an intended output capability of 24 W x 4 channels at THD = 10%. A digital amplifier controller can generate the PWM drive signals, while the STA51813TR supplies efficient current to the speaker outputs. The exposed thermal slug requires careful PCB copper and thermal-path design, and the output-filter component values must be selected together with the controller and speaker impedance.
Recommended
Multi-Channel Home Audio Amplifier
STA51813TR provides the configurable half-bridge resources needed for multi-channel home-audio output stages. Four half-bridges can be assigned as single-ended channels, paired into two full bridges, or reconfigured through the CONFIG connection to create a single bridge with doubled current capability. This flexibility supports compact receiver, amplifier, and powered-speaker platforms. Designers should calculate dissipation from the actual rail voltage, load impedance, duty cycle, and output waveform rather than relying only on the 24 W-per-channel headline rating. Speaker protection, DC blocking, and output filtering must also be integrated around the power stage.
Recommended
Powered Speaker Output Stage
The STA51813TR is appropriate for a powered-speek final stage when the enclosure can provide the required copper area or heatsinking for the exposed PowerSSO-36 thermal slug. Its 40 V supply rating accommodates many Class D output rails, while thermal, undervoltage, and short-circuit protections help manage common operating faults. The design must compare continuous speaker output with the thermal capability of the assembled PCB. For portable or thermally constrained products, reduce local output power, improve the thermal path, or select a package and stage more closely matched to the enclosure heat budget.
Recommended
Soundbar Multi-Channel Amplification
A soundbar can use the STA51813TR when its channel architecture benefits from four reconfigurable power half-bridges and the board has sufficient thermal capacity. The device can support multiway speaker arrangements without requiring four unrelated amplifier packages, helping simplify the power-stage layout. However, low-profile soundbar enclosures make exposed-pad heat spreading and copper area critical. Maintain short, low-inductance supply and ground connections, keep switching nodes compact, and verify that the controller's modulation scheme, dead time, and filtering match the intended Class D operating mode.
Recommended
Digital Speaker Amplifier Platform
STA51813TR serves as the power-conversion element in a digital speaker-amplifier platform where a digital audio processor performs modulation and the Class D output stage delivers energy to the load. Its CMOS-compatible logic inputs support integration with digital control systems, while the CONFIG pin provides an additional topology option beyond the standard quad-half-bridge arrangement. Designers should validate the controller's expected input format, switching frequency, timing requirements, and fault handling. The power stage also needs a carefully designed LC output filter, speaker protection network, and thermal implementation to prevent high-frequency switching energy from reaching the transducer.
Recommended
Compact Class D Audio Power Module
The STA51813TR can form the core of a compact Class D audio power module built around one PowerSSO-36 device. Its monolithic quad half-bridge topology reduces the number of separate output-driver packages, while the exposed pad allows heat to flow into the PCB rather than directly into the enclosure air. This approach suits custom amplifier boards and modular industrial audio products. The module designer must still reserve adequate copper area, implement via arrays under the thermal pad, select an appropriate inductor-capacitor output filter, and validate electromagnetic-emissions and thermal performance with the final enclosure and load.
Recommended
Recommended Products Summary
Engineering reference data for STA51813TR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product |
|---|---|
| Package | PowerSSO-36 with exposed bottom pad |
| Brand | STMicroelectronics |
| Maximum Supply Voltage | 40 V |
| Power Stage Current Capability | 3.5 A |
| Output Topology | Quad half-bridge, configurable as two bridges or one bridge |
| Process Technology | Multipower BCD |
| Output Stage | Complementary DMOS |
| Output Transistor RDS(on) | 200 mΩ |
| Maximum Output Power | 24 W x 4 channels at THD = 10% |
| Protection Functions | Thermal, thermal warning, undervoltage, and short-circuit protection |
Key Differentiators
- Flexible output topology (vs TDA7492MV13TR)
- Explicit 40 V power-stage rating (vs STA516B13TR)
- Integrated fault-management functions (vs MAX98400AETX+T)
Design Notes
Treat the exposed thermal slug as part of the electrical and mechanical design. Provide a continuous PCB thermal pad with multiple thermal vias and enough surrounding copper to conduct heat away from the junction. The package description identifies the slug as a direct path to a heatsink, so a board assembled without adequate copper may not sustain the advertised output-power condition. Validate the final enclosure, ambient temperature, load, and continuous-duty dissipation.
Place the output-stage supply and ground connections close to the package and use low-impedance planes or polygons. Keep the PWM and gate-drive paths away from sensitive audio inputs, and route the switching outputs with short, compact traces to reduce parasitic inductance and electromagnetic emissions. Follow the manufacturer land pattern and thermal-via recommendations rather than constructing a footprint only from the nominal 36-pin outline.
Design the output filter and speaker connection together with the digital amplifier controller. The controller's switching frequency and modulation strategy determine the required inductor and capacitor characteristics, while the output network should suppress switching ripple without creating excessive phase shift or instability. Confirm CONFIG, protection, and control connections against the manufacturer pin-description table before releasing the PCB artwork.
Do not assume that four half-bridges automatically mean four full-bridge outputs. Incorrect CONFIG logic or an unsuitable controller connection can produce the wrong channel topology. Also distinguish the 3.5 A device capability from continuous output power: rail voltage, load impedance, PWM duty cycle, thermal resistance, and waveform distortion determine the usable result. Review short-circuit and undervoltage behavior in the complete system design.
Compliance Information
The verified product information does not state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status. AEC-Q100 qualification is not identified; the device is an audio power stage rather than an explicitly automotive-qualified product in the available information.
