Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Audio amplifier 2-channel (stereo) with stereo headphones Class AB PDIP 20

www.ti.com

FEATURES DESCRIPTION

APPLICATIONS

-90

-80

-70

-60

-50

-40

-30

-20

-10

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

Volume [Pin 18] - V

DC VOLUME CONTROL

Volume - dB

BTL Volume

PGND

ROUT-

RIN+

RIN-

LIN-

LIN+

LOUT-

ROUT+

SE/BTL

VOLUME

AGND

BYPASS

FADE

SHUTDOWN

LOUT+

PGND

Right Positive

Differential Input Signal

Left Negative

Differential Input Signal

Right Negative

Differential Input Signal

Left Positive

Differential Input Signal

Power Supply

100 kW

330 F

0.47 Fm

10 F

0.47 F

(BYP)

In From DAC

Potentiometer

(DC Voltage)

System

Control

Right

Speaker

Left

Speaker

Headphones

1 kW

TPA6021A4

SLOS465 – JUNE 2005

2-W STEREO AUDIO POWER AMPLIFIER

WITH ADVANCED DC VOLUME CONTROL

• 2 W Into 4- Ω Speakers With External Heatsink

The TPA6021A4 is a stereo audio power amplifier

that drives 2 W/channel of continuous RMS power

• DC Volume Control With 2-dB

into a 4- Ω load when utilizing a heat sink. Advanced

Steps from -40 dB to 20 dB

dc volume control minimizes external components

– Fade Mode

and allows BTL (speaker) volume control and SE

– -85-dB Mute Mode

(headphone) volume control.

• Differential Inputs

The 20-pin DIP package allows for the use of a

• 1-µA Shutdown Current (Typical)

heatsink which provides higher output power.

• Headphone Mode

To ensure a smooth transition between active and

shutdown modes, a fade mode ramps the volume up

and down.

• LCD Monitors

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.

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 (25 pages)

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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 2-W STEREO AUDIO POWER AMPLIFIER WITH ADVANCED DC VOLUME CONTROL FEATURES • • • • • DESCRIPTION 2 W Into 4-Ω Speakers With External Heatsink DC Volume Control With 2-dB Steps from -40 dB to 20 dB – Fade Mode – -85-dB Mute Mode Differential Inputs 1-µA Shutdown Current (Typical) Headphone Mode The TPA6021A4 is a stereo audio power amplifier that drives 2 W/channel of continuous RMS power into a 4-Ω load when utilizing a heat sink.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. AVAILABLE OPTIONS PACKAGE TA 20-PIN PDIP (N) –40°C to 85°C TPA6021A4N ABSOLUTE MAXIMUM RATINGS over operating free-air temperature range (unless otherwise noted) (1) UNIT VSS Supply voltage, VDD, PVDD –0.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 RECOMMENDED OPERATING CONDITIONS VSS MIN MAX 4 5.5 Supply voltage, VDD, PVDD VIH High-level input voltage VIL Low-level input voltage TA Operating free-air temperature SE/BTL, FADE UNIT V 0.8 x VDD V 2 V SHUTDOWN SE/BTL, FADE 0.6 x VDD SHUTDOWN –40 V 0.8 V 85 °C MAX UNIT ELECTRICAL CHARACTERISTICS TA = 25°C, VDD = PVDD = 5.5 V (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP VDD = 5.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 N (PDIP) PACKAGE (TOP VIEW) PGND 1 20 ROUT- 2 19 SE/BTL PVDD 3 18 VOLUME RIN+ 4 17 AGND RINVDD 5 16 6 15 BYPASS FADE ROUT+ LIN- 7 14 SHUTDOWN LIN+ 8 13 NC PVDD 9 12 LOUT+ LOUT- 10 11 PGND Terminal Functions TERMINAL NAME NO.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 FUNCTIONAL BLOCK DIAGRAM RIN+ _ _ + ROUT+ + RIN- BYP + _ BYP _ + BYP SE/BTL VOLUME FADE ROUTEN SE/BTL Output Control Power Management 32-Step Volume Control PVDD PGND VDD BYPASS SHUTDOWN AGND LIN_ _ + LOUT- + LIN+ BYP + _ BYP _ + BYP LOUT+ EN SE/BTL NOTE: All resistor wipers are adjusted with 32 step volume control.
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TPA6021A4 www.ti.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 TOTAL HARMONIC DISTORTION + NOISE (SE) vs FREQUENCY 10 VDD = 5 V RL = 32 W Gain = 14 dB CI = 0.47 mF CO = 330 mF SE Stereo 5 2 1 0.5 PO = 75 mW 0.2 0.1 0.05 0.02 0.01 20 50 100 200 500 1k 2k 5 k 10 k 20 k THD+N - Total Harmonic Distortion + Noise (SE) - % THD+N - Total Harmonic Distortion + Noise (SE) - % TOTAL HARMONIC DISTORTION + NOISE (SE) vs FREQUENCY 10 VDD = 5 V RL = 10 kW Gain = 14 dB CI = 0.47 mF CO = 330 mF SE Stereo 5 2 1 0.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 TOTAL HARMONIC DISTORTION + NOISE (SE) vs OUTPUT VOLTAGE VDD = 5 V RL = 32 W Gain = 14 dB CI = 0.47 mF CO = 330 mF SE Stereo 5 2 1 0.5 20 Hz 0.2 20 kHz 0.1 0.05 1 kHz 0.02 0.01 10 20 30 40 50 100 10 THD+N - T otal Harmonic Distortion + Noise (SE) - % 10 200 VDD = 5 V RL = 10 kW Gain = 14 dB CI = 0.47 mF CO = 330 mF SE Stereo 5 2 1 0.5 0.2 0.1 20 Hz 0.05 0.02 0.01 0.005 1 kHz 0.002 0.001 0 0.2 0.4 PO - Output Power - mW 0.6 0.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 POWER DISSIPATION (PER CHANNEL) vs OUTPUT POWER POWER DISSIPATION (PER CHANNEL) vs OUTPUT POWER 200 VDD = 5 V BTL 1.8 PD - Power Dissipation (Per Channel) - mW PD - Power Dissipation (Per Channel) - W 2 1.6 1.4 1.2 4W 1 0.8 0.6 8W 0.4 0.2 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 140 120 100 16 W 80 60 32 W 40 20 0 2 0 50 100 150 200 PO - Output Power - W PO - Output Power - mW Figure 11. Figure 12.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 CROSSTALK vs FREQUENCY POWER SUPPLY REJECTION RATIO (BTL) vs FREQUENCY Crosstalk - dB -60 VDD = 5 V PO = 1 W RL = 8 W Gain = 20 dB BTL -80 Left to Right -100 Right to Left -120 -140 20 100 200 1k 2k PSRR - Power Supply Rejection Ratio (SE) - dB 0 -40 10 k 20 k VDD = 5 V RL = 8 W C(BYP) = 0.47 mF CI = 0.47 mF BTL -10 -20 -30 -40 -50 -60 Gain = 20 dB -70 -80 Gain = 0 dB -90 -100 20 100 Figure 16.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 APPLICATION INFORMATION SELECTION OF COMPONENTS Figure 19 and Figure 20 are schematic diagrams of typical LCD monitor application circuits. Right Speaker ROUT+ 1 CS 19 100 kW 3 Power Supply 1 kW PVDD 18 Right Audio Source Ci Ci 0.47 mF 0.47 mF 4 5 RIN+ RIN- VOLUME AGND C(BYP) 0.47 mF 6 Ci In From DAC or Potentiometer (DC Voltage) 17 VDD 0.47 mF 100 kW ROUT- 0.47 mF 10 mF CO 330 mF PGND SE/BTL 2 VDD 20 7 VDD BYPASS LINFADE 0.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 APPLICATION INFORMATION (continued) Right Speaker ROUT+ 1 PGND SE/BTL 2 CS Right Negative Differential Input Signal CO 330 mF 100 kW ROUT100 kW 3 Power Supply Right Positive Differential Input Signal 19 0.47 mF 10 mF VDD 20 1 kW PVDD 18 Ci 0.47 mF 4 Ci 0.47 mF 5 RIN+ RIN- VOLUME AGND In From DAC or Potentiometer (DC Voltage) 17 C(BYP) VDD 6 VDD BYPASS LIN- FADE 16 0.47 mF Headphones 0.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 APPLICATION INFORMATION (continued) 4 RIN+ _ _ + ROUT+ 20 + Bypass 5 RIN- Bypass VDD + _ _ ROUT- 2 + Bypass 100 kW CO 330 mF 1 kW EN SE/BTL 19 100 kW LOUT+ Figure 21. TPA6021A4 Resistor Divider Network Circuit Using a 1/8-in. (3,5 mm) stereo headphone jack, the control switch is closed when no plug is inserted. When closed the 100-kΩ/1-kΩ divider pulls the SE/BTL input low.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 When the FADE input is a logic low, the device is placed into fade-on mode. A logic high on this pin places the amplifier in the fade-off mode. The voltage trip levels for a logic low (VIL) or logic high (VIH) can be found in the recommended operating conditions table. When a logic low is applied to the FADE pin and a logic low is then applied on the SHUTDOWN pin, the channel gain steps down from gain step to gain step at a rate of two clock cycles per step.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 VOLUME OPERATION The VOLUME pin controls the BTL volume when driving speakers, and the SE volume when driving headphones. This pin is controlled with a dc voltage, which should not exceed VDD. The output volume increases in discrete steps as the dc voltage increases and decreases in discrete steps as the dc voltage decreases.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 INPUT RESISTANCE Each gain setting is achieved by varying the input resistance of the amplifier, which can range from its smallest value to over six times that value. As a result, if a single capacitor is used in the input high-pass filter, the –3 dB or cutoff frequency also changes by over six times. Rf C Ri IN Input Signal Figure 25. Resistor on Input for Cut-Off Frequency The input resistance at each gain setting is given in Figure 18.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 POWER SUPPLY DECOUPLING, C(S) The TPA6021A4 is a high-performance CMOS audio amplifier that requires adequate power supply decoupling to ensure the output total harmonic distortion (THD) is as low as possible. Power supply decoupling also prevents oscillations for long lead lengths between the amplifier and the speaker. The optimum decoupling is achieved by using two capacitors of different types that target different types of noise on the power supply leads.
PAGE 18
TPA6021A4 www.ti.com SLOS465 – JUNE 2005 As Table 2 indicates, most of the bass response is attenuated into a 4-Ω load, an 8-Ω load is adequate, headphone response is good, and drive into line level inputs (a home stereo for example) is exceptional. USING LOW-ESR CAPACITORS Low-ESR capacitors are recommended throughout this applications section. A real (as opposed to ideal) capacitor can be modeled simply as a resistor in series with an ideal capacitor.
PAGE 19
TPA6021A4 www.ti.com SLOS465 – JUNE 2005 In a typical computer sound channel operating at 5 V, bridging raises the power into an 8-Ω speaker from a singled-ended (SE, ground reference) limit of 250 mW to 1 W. In sound power that is a 6-dB improvement, which is loudness that can be heard. In addition to increased power there are frequency response concerns. Consider the single-supply SE configuration shown in Figure 27.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 IDD VO IDD(avg) V(LRMS) Figure 28. Voltage and Current Waveforms for BTL Amplifiers Although the voltages and currents for SE and BTL are sinusoidal in the load, currents from the supply are very different between SE and BTL configurations. In an SE application the current waveform is a half-wave rectified shape, whereas in BTL it is a full-wave rectified waveform. This means RMS conversion factors are different.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 Table 3. Efficiency vs Output Power in 5-V, 8-Ω BTL Systems OUTPUT POWER (W) EFFICIENCY (%) PEAK VOLTAGE (V) INTERNAL DISSIPATION (W) 0.25 31.4 2.00 0.55 0.50 44.4 2.83 0.62 1.00 62.8 4.00 0.59 1.25 70.2 4.47 (1) 0.53 (1) High peak voltages cause the THD to increase. A final point to remember about Class-AB amplifiers (either SE or BTL) is how to manipulate the terms in the efficiency equation to utmost advantage when possible.
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TPA6021A4 www.ti.com SLOS465 – JUNE 2005 Table 4. TPA6021A4 Power Rating, 5-V, 4-Ω Stereo (1) PEAK OUTPUT POWER (W) AVERAGE OUTPUT POWER POWER DISSIPATION (W/Channel) MAXIMUM AMBIENT TEMPERATURE 3 1500 mW (3 dB) 1.26 37°C 3 750 mW (6 dB) 1.20 42°C 3 380 mW (9 dB) 1.00 59°C 3 190 mW (12 dB) 0.79 79°C 3 95 mW (15 dB) 0.60 96°C (1) 3 48 mW (18 dB) 0.44 110°C (1) Package limited to 85°C ambient. Table 5.
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PACKAGE OPTION ADDENDUM www.ti.com 18-Jul-2006 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Eco Plan (2) Qty TPA6021A4N ACTIVE PDIP N 20 20 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type TPA6021A4NE4 ACTIVE PDIP N 20 20 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Lead/Ball Finish MSL Peak Temp (3) (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs.
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