TFA9815T/N1,118

Overview

The TFA9815T/N1,118 is a stereo full-bridge Class D audio amplifier power comparator manufactured by NXP USA Inc. It integrates two BTL power stages, drive logic, and protection circuits within a 32-lead SO plastic small outline package (SOT287-1). The device operates on an asymmetrical supply voltage ranging from 8 V to 20 V. It delivers up to 18 W per channel into a 4 Ω load at 12 V supply with 10% THD. Key electrical parameters include a sleep mode supply current of 110 μA typical, total quiescent current of 40 mA typical in operating mode, and output efficiency reaching 91% at 2 × 10 W into 8 Ω.

Feature Summary

• Stereo full-bridge architecture for high-efficiency Class D applications
• Zero dead-time switching capability
• Integrated thermal and current limiting without audible interruptions
• Supports both self-oscillating and open-loop system configurations

Applications

• Self-oscillating or open-loop Class D audio amplifier systems
• Flat-panel television sets
• Flat-panel monitors
• Multimedia systems
• Wireless speakers

Procurement Notes

Verify the specific ordering suffix

Selection Notes

Select this component for designs requiring a compact, heat-sink-free stereo amplifier solution. Ensure the application supports either self-oscillating or open-loop control topologies. Verify that the power supply provides a stable asymmetrical voltage between 8 V and 20 V. Confirm that the PCB layout accommodates the 32-lead SO package dimensions and utilizes sufficient copper area for thermal management as specified in the datasheet.

Part Context

The TFA9815 belongs to the TFA981 series of power comparators designed for digital audio amplification. It serves as a core building block for creating efficient Class D systems by combining power switching stages with differential input comparators. This integration allows for simplified system design compared to discrete solutions, reducing component count while maintaining high performance standards for consumer audio electronics.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.

FAQ

How does the TFA9815 handle overcurrent conditions?

The device features current-limiting protection that prevents audible interruptions. If the output current exceeds the threshold, the outputs become floating for 5 μs before resuming operation.

What is the difference between self-oscillating and open-loop modes?

In self-oscillating mode, the SO/OL pin is connected to VSSD(HW). In open-loop mode, the SO/OL pin is left floating, allowing external control logic to manage the switching frequency.