TPA301DR - 350mW Mono Class-AB Amplifier | Texas Instruments
MPN: TPA301DR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.16 | $1.16 |
| 10 | $1.05 | $10.50 |
| 100 | $0.91 | $91.00 |
| 500 | $0.82 | $410.00 |
| 1,000 | $0.74 | $740.00 |
TPA301DR Overview
Drop-in alternatives for TPA301DR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with TPA301DR (same form factor and footprint) — differing in Product Type, Shutdown Quiescent Current.
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No drop-in alternatives available for this product.
Request AlternativesTPA301DR Maximum Ratings & Electrical Characteristics
| Product Type | Mono audio power amplifier |
| Amplifier Class | Class AB |
| Output Power | 350 mW |
| Continuous Output Power at 3.3 V | 250 mW into 8 ohm BTL at less than 1% THD+N |
| Supply Voltage Operation | 3.3 V and 5 V |
| Output Configuration | Bridge-tied load (BTL), differential |
| Channel Count | 1 channel |
| Package | 8-pin SOIC |
| Mounting Type | Surface mount |
| Shutdown Quiescent Current | 0.15 microampere |
| Protection | Thermal and short-circuit protection |
| Frequency | 1.4 MHz |
TPA301DR Pin Configuration
| Pin 1 | NC — Not connected (per datasheet) |
| Pin 2 | NC — Not connected (per datasheet) |
| Pin 3 | IN+ — Noninverting audio input |
| Pin 4 | IN- — Inverting audio input |
| Pin 5 | SHUTDOWN — Shutdown control input |
| Pin 6 | BYPASS — Bypass capacitor connection |
| Pin 7 | OUT- — Negative bridge-tied-load output |
| Pin 8 | VDD — Positive supply voltage |
Typical Applications
TPA301DR is suitable for 6 applications: Portable Bluetooth Speaker, Voice-Enabled IoT Device, Compact Consumer Audio, USB Audio Accessory, Industrial Audible Alarm, Low-Voltage Educational Instrument.
Portable Bluetooth Speaker
The TPA301DR fits compact Bluetooth and portable speaker products powered from a 3.3 V rail because it delivers 250 mW continuously into an 8 ohm BTL load at less than 1% THD+N through the voice band. Place it between the audio codec or Bluetooth receiver and an internal speaker, with the two BTL outputs connected differentially. The Class-AB topology provides straightforward analog integration, while the 0.15 microampere shutdown quiescent current helps conserve battery energy when the system is off.
Recommended
Voice-Enabled IoT Device
TPA301DR is appropriate for voice-enabled IoT products that use a small internal speaker and a 3.3 V system rail. Its 350 mW class and 250 mW specified 3.3 V continuous output into 8 ohms provide useful headroom for alert tones, notifications, and speech playback without a large speaker. The bridge-tied-load connection should be routed as a differential pair, and the shutdown pin can be used to reduce supply consumption when the voice feature is inactive.
Recommended
Compact Consumer Audio
The TPA301DR can drive the internal speaker in a compact consumer product such as a personal audio accessory, learning device, or small tabletop unit. Its 3.3 V and 5 V operating focus matches common embedded supply rails, and the SOIC-8 package is straightforward for conventional surface-mount layouts. The Class-AB architecture avoids the filter and switching-node considerations of many Class-D amplifiers, but engineers should still budget for dissipation at low listening levels and verify the speaker impedance before layout release.
Recommended
USB Audio Accessory
TPA301DR is suitable for a USB-powered speaker or USB audio accessory when the available supply is 3.3 V or 5 V and the required acoustic power is approximately 250 to 350 mW. The device accepts an analog audio signal in the application architecture and drives a differential BTL speaker load. Designers should verify USB current limits, inrush behavior, cable grounding, and thermal rise during sustained low-level playback. The output pair must remain isolated from the USB ground because the BTL outputs switch differentially.
Recommended
Industrial Audible Alarm
An industrial audible alarm or status indicator can use TPA301DR when it is powered by a low-voltage regulated rail and uses a small 8 ohm speaker. The 350 mW device class is more than adequate for alert tones while the 3.3 V and 5 V specification simplifies supply selection. Use the shutdown control to disable the amplifier during idle periods, and verify the ambient temperature, enclosure temperature rise, speaker impedance, and maximum continuous duty cycle. Protection features help guard against thermal and short-circuit faults, but they do not replace correct wiring.
Recommended
Low-Voltage Educational Instrument
The TPA301DR is suitable for educational instruments, bench devices, and small teaching products that reproduce tones or voice prompts through an internal speaker. The 250 mW continuous 3.3 V rating is suitable for a compact 8 ohm transducer, while 5 V operation provides additional output capability when the power budget permits. Keep the input gain conservative to avoid distortion, terminate unused inputs according to the datasheet, and validate the speaker voltage waveform with an oscilloscope before production.
Recommended
Recommended Products Summary
Engineering reference data for TPA301DR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product |
|---|---|
| Brand | Texas Instruments |
| Package | 8-pin SOIC |
| Output Power | 350 mW |
| Continuous Power at 3.3 V | 250 mW into 8 ohm BTL at less than 1% THD+N |
| Supply Voltage | 3.3 V and 5 V |
| Channel Count | 1 channel mono |
| Output Configuration | Bridge-tied load (BTL) |
| Shutdown Quiescent Current | 0.15 microampere |
| Protection | Thermal and short-circuit protection |
| Specialization | Low-voltage internal-speaker application |
Key Differentiators
- Low-voltage mono Class-AB integration (vs TPA701DR)
- Defined 3.3 V continuous-load performance (vs TPA751DR)
- Shutdown-aware portable operation (vs General-purpose audio amplifiers without verified shutdown data)
Design Notes
Design the supply path for the BTL output current and maintain the manufacturer's recommended bypass arrangement close to VDD. Because the TPA301 is specified for 3.3 V and 5 V operation, verify the actual supply range under battery tolerance, USB variation, and load transients. Check the speaker voltage and current waveform at maximum volume before treating the nominal 350 mW class as guaranteed system output.
Route the two BTL speaker outputs as a differential pair and keep them away from sensitive input and microphone traces. Do not connect either output terminal to system ground. Place the input, gain-setting, and bypass components close to their associated pins, and use a solid ground plane that is not interrupted by the BTL output return path.
Class-AB amplifiers dissipate supply power even when the audible output level is low, so thermal design is essential in enclosed products. Use the manufacturer thermal information for the SOIC package, provide as much copper as practical, and estimate worst-case dissipation using the maximum supply, output voltage, load, and ambient temperature. Confirm that sustained alarm tones or voice playback does not drive the junction temperature beyond the device rating.
Compliance Information
The verified snippets identify RoHS and REACH only as search-result concepts for the family and do not provide an explicit TPA301DR compliance declaration. Verify current manufacturer documentation before making a regulatory claim.