User’s Guide February 2001 Mixed-Signal Products SLOU103A
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.
How to Use This Manual This document contains the following chapters: Chapter 1—Introduction Chapter 2—Operation Related Documentation From Texas Instruments 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.
Running Title—Attribute Reference This is an example of a warning statement. A warning statement describes a situation that could potentially cause harm to you.
Running Title—Attribute Reference 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Feature Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.
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Chapter 1 This chapter provides an overview of the Texas Instruments (TI) TPA0172 audio amplifier evaluation module (SLOP211). 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 Feature Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2 1.2 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Feature Highlights 1.
Description 1.2 Description The TPA0172 Stereo 2-W audio Ppower amplifier evaluation module is a complete, 2-Watt per channel stereo audio power amplifier. It consists of the TI TPA0172 Stereo 2-W audio power amplifier IC along with a small number of other parts and a D–25 connector mounted on a circuit board that measures approximately 2 1/4 inches by 2 inches (Figure 1–1). Figure 1–1.
TPA0172 EVM Specifications 1.3 TPA0172 EVM Specifications Supply voltage range, VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 V to 5.5 V Supply current, IDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 A max Continuous output power per channel, PO: 4-Ω BTL, VDD=5 V . . . . . . . . . . . . . . . . . . . . . . . . 2 W Audio input voltage, VI,: HP input . . . . . . . . . . . . . . . .
Chapter 2 Quick start lists in this chapter contain steps that can be followed to quickly prepare the TI plug-n-play audio amplifier evaluation platform for use with the TPA0172 audio amplifier EVM, or to connect the TPA0172 audio amplifier EVM for stand-alone operation. Using the TPA0172 audio amplifier evaluation module with the TI 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 TPA0172 EVM with the TI plug-n-play audio amplifier evaluation platform (see the platform user’s guide, SLOU011, for additional details). Typical platform switch and jumper settings are shown in Table 2–1 and typical EVM settings are shown in Table 2–2. Numbered callouts for selected steps are shown in Figure 2–1 and Figure 2–2. Platform preparations Table 2–1.
Quick Start List for Platform Evaluation Module Preparations Figure 2–2. Module Map P1 VDD Q1 TP5 R6 R HP TP3 GND R7 TP4 ROUT+ GND TP6 ROUT– Q2 GND R8 R9 R IN+ R5 S4 C12 12 TP1 C4 R4 C11 TP2 L LINE– GND 11 S3 U1 + C3 C1 C5 L IN+ SE/BTL R3 C2 C7 C6 C8 S2 R2 C10 1999 TEXAS INSTRUMENTS S1 SHUTDOWN R1 R LINE– LOUT– + L HP C9 VDD TPA0172 EVM Board GND SLOP211 Rev. A GND LOUT+ 11) Jumpers S2 and S3 select the least significant bits of the EVM I2C address. See section 2.
Quick Start List for Stand-Alone 2.3 Quick Start List for Stand-Alone Follow these steps to use the TPA0172 EVM stand-alone or when connecting it into existing circuits or equipment. Connections to the TPA0172 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. Typical EVM jumper settings are shown in Table 2–4. Numbered callouts for selected steps are shown in Figure 2–3. Figure 2–3.
Quick Start List for Stand-Alone Evaluation Module Preparations 6) Jumpers S2 and S3 select the least significant bits of the EVM I2C address. See section 2.5.3 for details. 7) To allow the module SE/BTL control input to switch the amplifier IC between single ended (SE) and bridge-tied load (BTL) output modes, set output mode jumper S4 to OFF. To keep the module amplifier IC in the single-ended output mode regardless of the control input state, set jumper S4 to ON. Table 2–4.
Stand-Alone Connection Diagram 2.4 Stand-Alone Connection Diagram The power supply range is 4.5 V to 5.5 V and isolated RO/MO+ and LO/MO– lines for BTL operation are required. Note that the source of any shutdown signal applied to the EVM SHUTDOWN pin must be able to sink the current flowing through the pullup resistor on the module (100 kΩ) when the pin is held low. Figure 2–4 shows a TPA0172 EVM connected for stereo BTL operation. Figure 2–4.
Reference 2.5 Reference This section includes the TPA0172 EVM schematic, the EVM parts list, a discussion of the I2C interface, and the module PCB layers. 2.5.1 EVM Schematic Figure 2–5 shows the TPA0172 EVM schematic. Figure 2–5. TPA0172 EVM Schematic Diagram VDD GND C10 PCBEEP TP2 0.47 µF 2 PCBEEP SHUTDOWN ADDRESS0 4 ADDRESS0 BYPASS 5 C8 0.47 µF C6 0.47 µF C7 0.47 µF LIN SHUTDOWN 21 C11 0.47 µF 20 C4 0.1 µF PVDD 7 LHP C1 C2 RIN+ RHP 0.47 µF C3 VDD 0.47 µF 9 0.
Reference 2.5.2 EVM Parts List Table 2–6 is the TPA0172 EVM parts list. Table 2–6. TPA0172 EVM Parts List Ref. C4, C5 Description Capacitor, 0.1 µF @ 25 V, 10%, nonpolarized C1 – C3, Capacitor, 0.47 µF @ 16 V C6 – C8, +80%/–20%, nonpolarized C10, C11 Size EVM Qty. Manufacturer/ Part Number 0805 2 Murata GRM40-X7R104K25 Arrow GRM40-X7R104K25 0805 8 Murata GRM40-Y5V474Z16 Arrow GRM40-Y5V474Z16 Vendor Number C9, C12 Capacitor, 10 µF @ 6.
Reference 2.5.3 I2C Interface Information The 8-bit I2C address of the TPA0172 is 11011a1a0(r/w). Bits 2 and 1, designated as a1 and a0, are set by the ADDRESS1 and ADDRESS0 pins, respectively. Bit 0, designated as (r/w), is the read/write bit where a 0 designates the write operation and a 1 designates the read operation. The TPA0172 has six 8-bit registers with power-up/reset values and bit assignments as shown in Table 2–7. Table 2–7.
Reference Data must be written to and read from these registers sequentially, in the order shown in the above table. This allows for a much shorter data stream, since the address for each register does not have to be sent/received and acknowledged before data can be written to or read from each register. For example, a typical write operation could be as follows: 1) 11011000 — Address of TPA0172 with write bit set 2) Acknowledge sent back by the TPA0172 3) 00000011 — Right gain register 1 set to 16.
Reference 2.5.3.2 Gain Register Operation The gain of the TPA0172 ranges from +20 dB to –60 dB in 64 1.25 dB steps. At power up, both the right and left channels are set at –60dB. The truth table shown in Table 2–8 gives examples of valid values that may be read from or written to the four gain setting registers. Note that the amplifier is muted if either bit 7 or bit 6 is set.
Reference 2.5.3.4 Control Register Operation Each bit of the control register allows the user to control the operating mode of the TPA0172, as shown in Table 2–9. Table 2–9.
Reference 2.5.4 Module PCB Layers The following illustrations depict the TPA0172 EVM PCB layers and silkscreen. These drawings are not to scale. Gerber plots can be obtained from any TI Sales Office. Figure 2–6. TPA0172 EVM PCB Figure 2–7.
Reference Figure 2–8.
2-16 Operation
