Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Audio amplifier 1-channel (mono) Class AB SOIC 8

www.ti.com

SHUTDOWN

BYPASS

IN+

IN-

GND

D OR DGN PACKAGE

(TOP VIEW)

DESCRIPTION

Audio

Input

Bias

Control

350 mW

BYPASS

IN -

0.1

SHUTDOWN

- 8

GND

From System Control

3 IN+

TPA321

SLOS312C – JUNE 2000 – REVISED JUNE 2004

350-mW MONO AUDIO POWER AMPLIFIER WITH DIFFERENTIAL INPUTS

• Fully Specified for 3.3-V and 5-V Operation

• Wide Power Supply Compatibility

2.5 V – 5.5 V

• Output Power for R

= 8 Ω

– 350 mW at V

= 5 V

– 250 mW at V

= 3.3 V

• Ultralow Supply Current in Shutdown

Mode . . . 0.15 µA

• Thermal and Short-Circuit Protection

• Surface-Mount Packaging

– SOIC

– PowerPAD™ MSOP

The TPA321 is a bridge-tied load (BTL) audio power amplifier developed especially for low-voltage applications

where internal speakers are required. Operating with a 3.3-V supply, the TPA321 can deliver 250 mW of

continuous power into a BTL 8-Ω load at less than 1% THD+N throughout voice band frequencies. Although this

device is characterized out to 20 kHz, its operation was optimized for narrower band applications such as cellular

communications. The BTL configuration eliminates the need for external coupling capacitors on the output in

most applications, which is particularly important for small battery-powered equipment. This device features a

shutdown mode for power-sensitive applications with a quiescent current of 0.15 µA during shutdown. The

TPA321 is available in an 8-pin SOIC surface-mount package and the surface-mount PowerPAD™ MSOP, which

reduces board space by 50% and height by 40%.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas

Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PowerPAD is a trademark of Texas Instruments.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.

Summary of content (30 pages)

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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 350-mW MONO AUDIO POWER AMPLIFIER WITH DIFFERENTIAL INPUTS • • • • • • Fully Specified for 3.3-V and 5-V Operation Wide Power Supply Compatibility 2.5 V – 5.5 V Output Power for RL = 8 Ω – 350 mW at VDD = 5 V – 250 mW at VDD = 3.3 V Ultralow Supply Current in Shutdown Mode . . . 0.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 ELECTRICAL CHARACTERISTICS at specified free-air temperature, VDD = 3.3 V, TA = 25°C (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX |VOO| Output offset voltage (measured differentially) SHUTDOWN = 0 V, RL = 8 Ω, RF = 10 kΩ PSRR Power supply rejection ratio VDD = 3.2 V to 3.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 Terminal Functions TERMINAL NAME I/O NO. I DESCRIPTION BYPASS is the tap to the voltage divider for internal mid-supply bias. This terminal should be connected to a 0.1-µF to 1-µF capacitor when used as an audio amplifier. BYPASS 2 GND 7 IN- 4 I IN- is the inverting input. IN- is typically used as the audio input terminal. IN+ 3 I IN+ is the noninverting input. IN+ is typically tied to the BYPASS terminal for SE operations.
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TPA321 www.ti.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 SUPPLY CURRENT (SHUTDOWN) vs SUPPLY VOLTAGE 0.5 SHUTDOWN = VDD RF = 10 kΩ I DD(SD)− Supply Current − µ A 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 2 2.5 3 3.5 4 4.5 5 5.5 5 5.5 VDD − Supply Voltage − V Figure 4. OUTPUT POWER vs SUPPLY VOLTAGE 1000 THD+N 1% PO − Output Power − mW 800 600 RL = 8 Ω 400 RL = 32 Ω 200 0 2 2.5 3 3.5 4 4.5 VDD − Supply Voltage − V Figure 5.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 OUTPUT POWER vs LOAD RESISTANCE 800 THD+N = 1% 700 PO − Output Power − mW 600 VDD = 5 V 500 400 300 VDD = 3.3 V 200 100 0 8 16 24 32 40 48 56 64 RL − Load Resistance − Ω Figure 6. TOTAL HARMONIC DISTORTION + NOISE vs FREQUENCY TOTAL HARMONIC DISTORTION + NOISE vs FREQUENCY 10 VDD = 3.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER 10 THD+N −Total Harmonic Distortion + Noise − % THD+N −Total Harmonic Distortion + Noise − % 10 VDD = 3.3 V f = 1 kHz AV = −2 V/V 1 RL = 8 Ω 0.1 0.01 0.04 0.1 0.16 0.22 0.28 0.34 f = 20 kHz f = 10 kHz 1 f = 1 kHz 0.1 f = 20 Hz 0.01 0.01 0.4 0.1 Figure 9. Figure 10.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER 10 THD+N −Total Harmonic Distortion + Noise − % VDD = 5 V f = 1 kHz AV = −2 V/V 1 RL = 8 Ω 0.1 0.25 0.40 0.55 0.70 0.85 f = 20 kHz f = 10 kHz 1 f = 1 kHz 0.1 f = 20 Hz VDD = 5 V RL = 8 Ω AV = −2 V/V 0.01 0.01 1 0.1 1 PO − Output Power − W PO − Output Power − W Figure 13. Figure 14.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 OPEN-LOOP GAIN AND PHASE vs FREQUENCY 40 180 VDD = 5 V RL = Open Phase 30 120 20 60 10 0 0 Phase − ° Open-Loop Gain − dB Gain −60 −10 −120 −20 −30 −180 1 101 102 103 104 f − Frequency − kHz Figure 16. CLOSED-LOOP GAIN AND PHASE vs FREQUENCY 1 180 Phase 0.75 170 0.25 0 160 Gain −0.25 150 −0.5 −0.75 140 −1 −1.25 −1.5 −1.75 −2 101 VDD = 3.3 V RL = 8 Ω PO = 0.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 CLOSED-LOOP GAIN AND PHASE vs FREQUENCY 1 180 Phase 0.75 170 0.25 0 160 Gain −0.25 150 −0.5 −0.75 Phase − ° Closed-Loop Gain − dB 0.5 140 −1 VDD = 5 V RL = 8 Ω PO = 0.35 W CI =1 µF −1.25 −1.5 −1.75 −2 101 102 130 103 104 105 120 106 f − Frequency − Hz Figure 18. OUTPUT NOISE VOLTAGE vs FREQUENCY 100 VDD = 3.3 V BW = 22 Hz to 22 kHz RL = 32 Ω CB =0.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 POWER DISSIPATION vs OUTPUT POWER 300 720 270 640 PD − Power Dissipation − mW PD − Power Dissipation − mW POWER DISSIPATION vs OUTPUT POWER 240 210 180 150 VDD = 3.3 V RL = 8 Ω 120 480 400 320 VDD = 5 V RL = 8 Ω 240 90 160 0 100 200 300 PO − Output Power − mW Figure 21. 12 560 400 0 200 400 600 800 PO − Output Power − mW Figure 22.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 APPLICATION INFORMATION BRIDGE-TIED LOAD Figure 23 shows a linear audio power amplifier (APA) in a BTL configuration. The TPA321 BTL amplifier consists of two linear amplifiers driving both ends of the load. There are several potential benefits to this differential drive configuration but power to the load should be initially considered.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 APPLICATION INFORMATION (continued) VDD -3 dB VO(PP) CC RL VO(PP) fc Figure 24. Single-Ended Configuration and Frequency Response Increasing power to the load does carry a penalty of increased internal power dissipation. The increased dissipation is understandable considering that the BTL configuration produces 4× the output power of a SE configuration.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 APPLICATION INFORMATION (continued) P Efficiency where PL P V L RMS R L L SUP 2 Vp 2 2R L V V P L RMS 2 P SUP VDD I DD RMS I DD RMS V DD 2VP RL 2V P RL (3) Efficiency of a BTL configuration VP 2V DD P LR L 2 1 2 2V DD (4) Table 1 employs Equation 4 to calculate efficiencies for three different output power levels.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 APPLICATION SCHEMATICS Figure 26 is a schematic diagram of a typical handheld audio application circuit, configured for a gain of –10 V/V. VDD 6 RF 50 kΩ CF 5 pF Audio Input CI RI 0.47 µF 10 kΩ 4 IN - 3 IN+ 2 BYPASS VDD CS VDD/2 1 µF - VO+ 5 + CB 2.2 µF - VO- + 8 350 mW 7 GND 1 From System Control SHUTDOWN Bias Control Figure 26.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 COMPONENT SELECTION Gain Setting Resistors, RF and RI The gain for each audio input of the TPA321 is set by resistors RF and RI according to Equation 5 for BTL mode. R F BTL Gain A V 2 R I (5) BTL mode operation brings about the factor 2 in the gain equation due to the inverting amplifier mirroring the voltage swing across the load.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 −3 dB fc 1 2 R C I I fc (8) The value of CI is important to consider as it directly affects the bass (low-frequency) performance of the circuit. Consider the example where RI is 10 kΩ and the specification calls for a flat bass response down to 40 Hz. Equation 8 is reconfigured as Equation 9. 1 C I 2 R f c I (9) In this example, CI is 0.40 µF, so one would likely choose a value in the range of 0.47 µF to 1 µF.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 USING LOW-ESR CAPACITORS Low-ESR capacitors are recommended throughout this application. A real (as opposed to ideal) capacitor can be modeled simply as a resistor in series with an ideal capacitor. The voltage drop across this resistor minimizes the beneficial effects of the capacitor in the circuit. The lower the equivalent value of this resistance, the more the real capacitor behaves like an ideal capacitor. 5-V VERSUS 3.
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TPA321 www.ti.com SLOS312C – JUNE 2000 – REVISED JUNE 2004 Table 2. TPA321 Power Rating, 5-V, 8-Ω BTL MAXIMUM AMBIENT TEMPERATURE PEAK OUTPUT POWER (mW) AVERAGE OUTPUT POWER POWER DISSIPATION (mW) 350 350 mW 600 46°C 350 175 mW (3 dB) 500 64°C 350 88 mW (6 dB) 380 85°C 350 44 mW (9 dB) 300 98°C 350 22 mW (12 dB) 200 115°C 350 11 mW (15 dB) 180 119°C 0 CFM Table 2 shows that the TPA321 can be used to its full 350-mW rating without any heat sinking in still air up to 46°C.
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.com 11-Apr-2013 (4) Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Top-Side Marking for that device. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided.
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PACKAGE MATERIALS INFORMATION www.ti.com 26-Jan-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant TPA321DGNR MSOPPower PAD DGN 8 2500 330.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 TPA321DR SOIC D 8 2500 330.0 12.4 6.4 5.2 2.1 8.0 12.
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PACKAGE MATERIALS INFORMATION www.ti.com 26-Jan-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) TPA321DGNR MSOP-PowerPAD DGN 8 2500 358.0 335.0 35.0 TPA321DR SOIC D 8 2500 367.0 367.0 35.
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IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.