Texas Instruments APA100 manual TAS5111 H-Bridge, TLV2464A Gain Setting and Feedback

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TAS5111 (H-Bridge)

For more information concerning the TPA2001D1 operation and modulation scheme, see the TPA2001D1 data sheet

http://focus.ti.com/docs/prod/folders/print/tpa2001d1.html

4.3 TAS5111 (H-Bridge)

The TAS5111 converts the PWM signal from the 3-V peak-to-peak outputs of the TPA2001D1 to 18-V to 29.5-V peak-to-peak. This allows the output power to increase from 1 W with just the TPA2001D1 to 100 W with the TAS5111 H-bridge. The TAS5111 has short-circuit and thermal protection. It is a high-performance H-bridge designed for audio with fast rise and fall times and well−matched output MOSFETs. Therefore, the TAS5111 adds little distortion to the system. To obtain peak TAS5111 performance, the schematic and layout of this reference design must be followed precisely.

For more information on the TAS5111 H-bridge and TAS5111 layout tips, see the TAS5111 data sheet.

http://focus.ti.com/docs/prod/folders/print/tas5111.html

4.4 TLV2464A (Gain Setting and Feedback)

The choice of the op amp in this system is critical. The TLV2464A is a low-noise, high-current, rail-to-rail output quad op amp. The TLV2464A was chosen because it meets the following list of critical op amp specifications at a reasonable price:

1)Rail-to-rail output

2)High output current

3)Low noise < 15 nV/sqrt (Hz)

4)Low input offset voltage < 3 mV

5)Low input base current

6)Gain bandwidth > 4 MHz

7)High slew rate > 1 V/∝s

The op amp needs to have rail-to-rail outputs because the outputs will rail when there is signal but TAS5111 is in RESET. High output current is important because it less susceptible to the switching noise that could cause signal lines of a low current op amp to be corrupted. Using a low current op amp greatly increases noise and distortion, often to the point of nonfunctionality. Low offset voltage is needed because the integrator has a DC gain of 100 V/V, and the integrator needs to be set at mid level. Low input base current (IIB) is important to limit offset for the same reason. Low noise is obviously important to limit the noise of the system because the op amp contributes noise in the gain stage, the integrator, the feedback (/45), and the midsupply generator. High gain bandwidth and slew rate are important to limit distortion and help with stability.

Technical Information

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Contents User’s Guide Important Notice About This Manual Read This FirstRelated Documentation From Texas Instruments Contents Tables FiguresEVM Overview Power Requirements Features2 TPA2001D1 and TLV2464A Supply Voltage 3-V Reference EVM Basic Function/Block Diagram−2. APA100 EVM Block Diagram PCB Design Split Ground Plane PCB LayoutBridge Layout PCB Layers −4. Bottom Copper and Silkscreen Bill of Materials −1. Parts ListSchematic Page EVM Operation Quick Start Power SupplyReset Button/Mute Power−Up/Down SequenceError Signals Changing the Gain Technical Information Feedback System Design −1 shows the block diagram of the feedback loop−2. Open− and Closed−Loop Frequency Response −4. APA100 Integrator Design Feedback System Design −5. Pspice Circuit for Simulating the Feedback −6. Pspice Simulation of Open−Loop Response TPA2001D1 Class-D Modulator−7. TPA2001D1 Block Diagram TAS5111 H-Bridge TLV2464A Gain Setting and Feedback−9. APA100 Output Filter LC Filter−1. TAS5111 Thermal Table ThermalThermal Measured Results −1. APA100 THD+N vs Frequency With 4- W Load Total Harmonic Distortion + Noise−3. APA100 THD+N vs Output Power With 4- W Load −5. APA100 Output Power vs Supply Voltage With 4- W Load Output PowerEfficiency −7. APA100 Efficiency vs Output Power With 4- W LoadSignal-to-Noise Ratio SNR Gain and Phase ResponseSupply Ripple Rejection

APA100 specifications

Texas Instruments is known for its innovation in the field of analog and embedded processing, with the APA100 being one of its noteworthy products. The APA100 is an advanced analog front-end (AFE) device designed to meet the needs of various applications including industrial, automotive, medical, and consumer electronics.

One of the standout features of the APA100 is its high-resolution data conversion capability. It integrates both analog-to-digital converters (ADCs) and digital-to-analog converters (DACs), providing unmatched precision and accuracy in signal processing. The device supports multiple sampling rates, which allows it to adapt to various requirements in different applications, ensuring optimal performance.

The power efficiency of the APA100 is another significant characteristic. Designed with low-power consumption in mind, it enables battery-operated devices to maximize their lifespan while maintaining reliable performance. This energy efficiency makes the APA100 suitable for wearables and portable medical devices, where power management is critical.

In addition to its power efficiency, the APA100 features integrated signal conditioning, which includes amplifiers and filters that enhance the quality of the input signals. This capability reduces the need for external components, thereby simplifying system design and reducing overall costs. With its built-in signal conditioning, engineers can expect improved accuracy and reduced noise in their measurements.

Texas Instruments has also included advanced communication interfaces in the APA100, such as SPI and I2C, to facilitate seamless integration with microcontrollers and processors. This flexibility allows for easy implementation into existing systems, enabling developers to take full advantage of the device's features without extensive re-engineering.

The APA100 is also designed for robustness, featuring a wide operating temperature range, making it suitable for use in harsh environments. This reliability is crucial for industrial applications where device performance can be affected by temperature fluctuations.

Overall, the Texas Instruments APA100 is an exceptional analog front-end device that combines high precision, low power consumption, integrated signal conditioning, and robust design. Its versatile features make it an ideal choice for various applications, paving the way for advancements in technology and improved performance across different sectors. With the APA100, engineers have a powerful tool that can help them innovate and enhance their products in highly competitive markets.
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