Texas Instruments TPA301 manual Signal Routing, Signal Conditioning

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Using The TPA301 EVM With the Plug-N-Play Evaluation Platform

3.3.2Signal Routing

Signal flow on the platform is controlled by two signal routing switches, as shown in Figure 3 –5.

Figure 3–5. Platform Signal Routing and Outputs

R

 

Audio

U1

Signal

Input

Conditioning

 

L

 

Off

S2

On

U3

 

 

+

 

TPA301

R

 

R

 

Amplifier EVM

 

J7, J8, J9

 

 

 

 

 

 

 

 

Speaker

U4

 

 

Outputs

 

 

 

TPA301

L

 

L

 

Amplifier EVM

 

+

 

 

U2 – U4

 

 

 

 

 

 

R

 

U5

R

 

+

 

Stereo

 

GND

J10

Headphone

S3

 

Headphone

 

 

Amplifier

L

 

Output

 

 

 

+

 

 

 

 

L

 

 

U5

 

 

 

3.3.2.1Signal Conditioning

The audio signal from the input jacks can be applied to the signal conditioning socket (U1) if an EVM is installed there, or socket U1 can be bypassed and the audio-input signal applied directly to the inputs of the TPA301 power amplifiers.

Switch S2 selects signal conditioning or bypasses it

3.3.2.2Headphone Output Jack

Switch S3 is the source select for the stereo headphone output jack, J10. The headphone jack is capacitively coupled (via 470 F electrolytics) and can output either the signal from the headphone amplifier in socket U5, or the signal from the TPA301 power amplifiers installed in sockets U3 and U4, as determined by the setting of headphone source select switch S3.

When S3 is set to the power amplifier position (U2 – U4), the headphone jack is connected to the TP301 power amplifier OUT+ output lines. When a plug is inserted into the jack, signals output through J10 are returned to platform ground, requiring single-ended power amplifier operation. A switch inside the headphone jack produces a control signal that can be routed to the power amplifier sockets to shut down the TPA301 EVMs when a plug is inserted.

Source select switch S3 connects the headphone jack to the output lines of either the headphone amplifier socket U5, or the power amplifier sockets (U2 J– U4).

To keep the TPA301 amplifier outputs separated, set switch S3 to the headphone amplifier position (U5 ) and use the speaker outputs (J7,

JJ8, and J9)

To route the TPA301 amplifier outputs to the headphone output jack (J10), set switch S3 to the power amplifier position (U2 – U4 ) and reverse the jumper on JP8 to prevent muting of the TPA301 module when a plug is inserted into J10 — use this setting only if the TPA301 EVMs are to drive single-ended loads connected to J10

Details 3-7

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Contents User’s Guide Important Notice Related Documentation FromJTexas Instruments PrefacePage Contents Tables FiguresIntroduction Feature Highlights Description TPA301 EVM SpecificationsIntroduction JP6 JP7 JP8 Quick StartPower PrecautionsPlatform preparations Quick Start List for PlatformQuick Start List for Stand-Alone Details TI Plug-N-Play Audio Amplifier Evaluation Platform TPA301 EVM TPA301 Audio Power Amplifier Evaluation Module1 TPA301 Audio Amplifier IC BTL OperationSIngle-Ended Operation Shutdown Module GainEVM Insertion Installing and Removing EVM BoardsSignal Conditioning Signal RoutingMuting Headphone Jack Control SignalsPower Requirements Inputs Inputs and Outputs1 TPA301 EVM Connected for BTL Output Using The TPA301 EVM Stand-AloneTPA301 EVM Connected for Stereo Single-Ended Output 2 TPA301 EVM Connected for Single-Ended OutputTPA301 EVM Parts List TPA301 Audio Power Amplifier Evaluation Module Parts ListDetails

TPA301 specifications

Texas Instruments TPA301 is a highly efficient, low-power audio amplifier designed for portable audio applications. This device is particularly well-suited for mobile phones, tablets, and other compact audio systems where space is limited but sound quality remains a priority. The TPA301 sits at the intersection of advanced audio technology and user-friendliness, making it a go-to choice for designers seeking a high-performance solution.

One of the main features of the TPA301 is its Class D architecture, which offers superior energy efficiency compared to traditional Class AB amplifiers. This means that less power is wasted as heat, allowing for longer battery life in portable devices. The TPA301 delivers up to 1.5W per channel into an 8-ohm load at low-distortion levels, ensuring that consumers experience clear audio reproduction, even at high volumes.

Furthermore, the TPA301 integrates several advanced technologies, including a built-in digital signal processor (DSP) that enables sophisticated audio processing capabilities. This DSP allows for features like active noise cancellation and equalization, enhancing the listening experience by tailoring the audio output according to the environment. The device also supports various audio inputs, including I2S, PCM, and TDM formats, providing design flexibility for developers.

The TPA301 is designed with a focus on compactness and thermal management, featuring a small package size that makes it ideal for space-constrained applications. Additionally, its low quiescent current contributes to minimal power consumption when the amplifier is in standby mode, making it a perfect fit for portable gadgets where battery longevity is critical.

Another notable characteristic of the TPA301 is its robust protection features, including over-temperature protection, short-circuit protection, and under-voltage lockout. These safety mechanisms ensure reliable operation under various conditions, protecting both the amplifier and connected speakers from damage.

In summary, Texas Instruments TPA301 stands out as an efficient, compact audio amplifier designed specifically for portable applications. Its combination of Class D efficiency, built-in DSP capabilities, wide audio format support, and comprehensive protection features make it an excellent choice for designers aiming for high-quality audio in a small footprint. Whether in smartphones or tablets, the TPA301 ensures consumers enjoy an unparalleled audio experience.