TPA122 MSOP Audio Power Amplifier Evaluation Module User’s Guide 1998 Mixed-Signal Products SLOU025
IMPORTANT NOTICE Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete.
Preface Related Documentation From Texas Instruments J J TI Plug-N-Play Audio Amplifier Evaluation Platform (literature number SLOU011) provides detailed information on the evaluation platform and its use with TI audio evaluation modules. TPA122 150-mW STEREO AUDIO POWER AMPLIFIER (literature number SLOS211) This is the data sheet for the TPA122 audio amplifier integrated circuit. FCC Warning This equipment is intended for use in a laboratory test environment only.
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Running Title—Attribute Reference Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Feature Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.
Running Title—Attribute Reference Figures 1–1 2–1 2–2 3–1 3–2 3–3 3–4 3–5 3–6 3–7 3–8 The TI TPA122 MSOP Audio Amplifier Evaluation Module . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 Quick Start Platform Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 Quick Start Module Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 1 Introduction This chapter provides an overview of the Texas Instruments (TI) TPA122 MSOP Audio Amplifier Evaluation Module (SLOP125). It includes a list of EVM features, a brief description of the module illustrated with a pictorial diagram, and a list of EVM specifications. Topic Page 1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2 1.2 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Features 1.1 Features The TI TPA122 MSOP Audio Amplifier Evaluation Module and the TI Plug-N-Play Audio Amplifier Evaluation Platform include the following features: - TPA122 MSOP Stereo Audio Power Amplifier Evaluation Module J J J J J J J - J J J J - 1-2 150-mW output power into 8 Ω at 5 V 2.5-V to 5.5-V operation Very low distortion — THD+N is less than 0.006% @ 1 kHz and less than 0.07% from 20 Hz to 20 kHz into 10-kΩ loads; less than 0.02% @ 1 kHz and less than 0.
Description 1.2 Description The TPA122 MSOP Audio Power Amplifier Evaluation Module is a complete, low-power stereo audio power amplifier for high-fidelity line-level output, headphone, and small speaker applications. It consists of the TI TPA122 150-mW Stereo Audio Power Amplifier IC in a very small MSOP package, along with a small number of other parts mounted on a circuit board that is approximately one and a quarter inches square (Figure 1–1). Figure 1–1.
1-4 Introduction
Chapter 2 Quick Start The steps in this chapter can be followed to quickly prepare the TPA122 MSOP audio amplifier EVM for use. Using the TPA122 MSOP EVM with the TI Plug-N-Play Audio Amplifier Evaluation Platform is a quick and easy way to connect power, signal and control inputs, and signal outputs to the EVM using standard connectors.
Precautions 2.1 Precautions Power Supply Input Polarity and Maximum Voltage Always ensure that the polarity and voltage of the external power connected to VCC power input connector J1, J2, and/or VDD power input connector J6 are correct. Overvoltage or reverse-polarity power applied to these terminals can open onboard soldered-in fuses and cause other damage to the platform, installed evaluation modules, and/or the power source.
Quick Start List for Platform 2.2 Quick Start List for Platform - Follow these steps when using the TPA122 MSOP EVM with the TI Plug-N-Play Audio Amplifier Evaluation Platform (see the platform user’s guide, SLOU011, for additional details). Numbered callouts for selected steps are shown in Figure 2–1 and details appear in Chapter 3. Platform preparations 1) Ensure that all external power sources are set to OFF and that the platform power switch S1 is set to OFF.
Quick Start List for Stand-Alone 2.3 Quick Start List for Stand-Alone Follow these steps to use the TPA122 MSOP EVM stand-alone or when connecting it into existing circuits or equipment. Connections to the TPA122 MSOP module header pins can be made via individual sockets, wire-wrapping, or soldering to the pins, either on the top or the bottom of the module circuit board (Figure 2–2). Details appear in Chapter 3. Figure 2–2.
Chapter 3 Details This chapter provides details on the TPA122 IC, the evaluation module, the steps in the Quick-Start List, additional application information, and a parts list for the TPA122 MSOP evaluation module. Topic Page 3.1 Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2 3.2 The TPA122 MSOP Audio Power Amplifier Evaluation Module . . . . 3–3 3.3 Using The TPA122 MSOP EVM With The Plug-N-Play Evaluation Platform . . . . . . .
Precautions 3.1 Precautions Power Supply Input Polarity and Maximum Voltage Always ensure that the polarity and voltage of the external power connected to VCC power input connector J1, J2, and/or VDD power input connector J6 are correct. Overvoltage or reverse-polarity power applied to these terminals can open onboard soldered-in fuses and cause other damage to the platform, installed evaluation modules, and/or the power source.
The TPA122 MSOP Audio Power Amplifier Evaluation Module 3.2 The TPA122 MSOP Audio Power Amplifier Evaluation Module The TPA122 MSOP Audio Power Amplifier Evaluation Module is powered by a TPA122 150-mW Stereo Audio Amplifier IC. It includes a shutdown control signal input with onboard switch and can drive either line-level outputs, 32-Ω headphones, or 8-Ω speakers.
The TPA122 MSOP Audio Power Amplifier Evaluation Module 3.2.1 TPA122 Audio Amplifier IC The TPA122 audio amplifier IC is a CMOS device intended primarily for high-performance line-level output, headphone driver, and small speaker applications. It is supplied in a very small surface-mount MSOP package and has been designed to operate from low supply voltages (between approximately 2.5 V and 5.5 V) and to deliver up to approximately 150 mW into 8-Ω speakers with low distortion.
The TPA122 MSOP Audio Power Amplifier Evaluation Module 3.2.2 Module Gain The TPA122 MSOP evaluation module has a set gain of 4 (inverting) for each channel. However, the gain can be adjusted to a maximum of approximately 10 (inverting) by changing the value of feedback resistors (R2 and R4, Figure 3–3). Use the following equation to determine the value of RF: Gain + – RR F I The TPA122 amplifier IC, like most other amplifiers, exhibits its best distortion and noise performance at lower gain levels.
Using The TPA122 MSOP EVM With the Plug-N-Play Evaluation Platform 3.3 Using The TPA122 MSOP EVM With the Plug-N-Play Evaluation Platform The TPA122 MSOP Audio Amplifier Evaluation Module is designed for use with the TI Plug-N-Play Audio Amplifier Evaluation Platform. It simply plugs into socket U5. The following paragraphs provide additional details for using the TPA122 EVM with the platform. 3.3.
Using The TPA122 MSOP EVM With the Plug-N-Play Evaluation Platform 3.3.2 Signal Routing Signal flow on the platform is controlled by two signal routing switches, as shown in Figure 3 – 5. Figure 3–5.
Using The TPA122 MSOP EVM With the Plug-N-Play Evaluation Platform 3.3.3 Shutdown The TPA122 MSOP EVM is equipped with a shutdown control input pin. When this input is tied to VDD, the TPA122 amplifier IC on the module ceases operation and enters an ultra-low-power state. When the EVM shutdown control input is tied to GND or allowed to float, amplifier operation resumes.
Using The TPA122 MSOP EVM With the Plug-N-Play Evaluation Platform 3.3.4 Power Requirements The TPA122 MSOP Audio Power Amplifier Evaluation Module can operate from a VDD voltage between approximately 2.5 V and 5.5 V. The TI Plug-N-Play Audio Amplifier Evaluation Platform with a voltage regulator EVM installed on it can provide a regulated 3.3-V or 5-V VDD supply from a wide variety of unregulated VCC voltage inputs between approximately 5.5 V and 12 V, including an onboard 9 -V battery.
Using The TPA122 MSOP EVM With the Plug-N-Play Evaluation Platform 3.3.5 Inputs and Outputs The TI Plug-N-Play Audio Amplifier Evaluation Platform is equipped with several standard conectors for audio inputs and outputs. 3.3.5.1 Inputs In most cases, audio signals enter the platform through either a pair of RCA phono jacks (J3 and J5) or a miniature (1/8″) stereo phone jack (J4).
Using The TPA122 MSOP EVM Stand-Alone 3.4 Using The TPA122 MSOP EVM Stand-Alone Using the TPA122 MSOP Audio Power Amplifier Evaluation Module stand-alone is much the same as using it with the platform. The same 2.5-V to 5.5-V power supply requirement exists. Note that the shutdown signal applied to the EVM SD pin must be able to supply enough current to overcome the pulldown resistor on the module (20 kΩ). 3.4.1 TPA122 MSOP EVM Connected as a Stereo Headphone Amplifier Figure 3–8.
TPA122 MSOP Audio Power Amplifier Evaluation Module Parts List 3.5 TPA122 MSOP Audio Power Amplifier Evaluation Module Parts List Table 3–1. TPA122 MSOP EVM Parts List Description Size EVM Qty. C1, C2, C3, C4 Capacitor, 1 µF, 80%/–20%, nonpolarized, SMD 0603 4 Murata GRM39-Y5V105Z10PT Newark C5 Capacitor, 10 µF, 6.
