TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 17-W MONO FILTER-FREE CLASS-D AUDIO POWER AMPLIFIER FEATURES D 17 W Into 8-Ω Load From 18-V Supply D Third-Generation Modulation Technique: D D D D D DESCRIPTION The TPA3000D1 is a 17-W mono bridge-tied load (BTL) filter-free class-D audio power amplifier with high efficiency, eliminating the need for heatsinks. The TPA3000D1 is designed to drive speakers without an output filter. – Filter-Free Operation – Improved Efficiency – Improved SNR Low Supply Current . . . 8 mA Typ at 12 V Shutdown Control . . . <1 µA Typ Shutdown Pin Is TTL Compatible TA = –40°C to 85°C Space-Saving, Thermally-Enhanced PowerPAD Packaging The gain of the amplifier is controlled by two input terminals, GAIN1 and GAIN0. This allows the amplifier to be configured for a gain of 12, 18, 23.6, and 36 dB. The differential input stage provides high common mode rejection and improved power supply rejection. The amplifier also includes depop circuitry to reduce the amount of turnon pop at power-up and when cycling SHUTDOWN. APPLICATIONS D LCD Monitors D Hands-Free Car Kits D Powered Speakers The TPA3000D1 is available in the 24-pin thermally enhanced TSSOP package (PWP) which eliminates the need for an external heat sink when playing music. EFFICIENCY vs OUTPUT POWER OUTPUT POWER vs SUPPLY VOLTAGE 100 17 90 15 80 PO – Output Power – W RL = 8 Ω Speaker Efficiency – % 70 60 50 40 30 13 11 RL = 8 Ω 9 7 20 0 0 3 6 9 12 VCC = 8 V TO 18 V f = 1 kHz Maximum 1% THD+N 5 VCC = 15 V f = 1 kHz 10 15 PO – Output Power – W 3 8 10 12 14 16 18 VCC – Supply Voltage – V 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. Copyright 2002, Texas Instruments Incorporated PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. www.ti.com 1 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 AVAILABLE OPTIONS PACKAGED DEVICES TSSOP (PWP)† TA – 40°C to 85°C TPA3000D1PWP † The PWP package is available taped and reeled. To order a taped and reeled part, add the suffix R to the part number (e.g., TPA3000D1PWPR). PWP PACKAGE (TOP VIEW) 1 2 3 4 5 6 7 8 9 10 11 12 INN INP GAIN0 GAIN1 SHUTDOWN PGND VCLAMP BSN PVCC OUTN OUTN PGND 24 23 22 21 20 19 18 17 16 15 14 13 VCC VREF BYPASS COSC ROSC AGND AGND BSP PVCC OUTP OUTP PGND Terminal Functions TERMINAL NAME AGND NO. I/O 18, 19 DESCRIPTION Analog ground BSN 8 I Bootstrap pin for high-side gate drive of negative BTL output (connect a 10-nF capacitor from OUTN to BSN) BSP 17 I Bootstrap pin for high-side gate drive of positive BTL output (connect a 10-nF capacitor from OUTP to BSP) BYPASS 22 I Connect 0.47 µF capacitor to ground for BYPASS voltage filtering. COSC 21 I Connect a 220-pF capacitor to ground to set oscillation frequency. GAIN0 3 I Bit 0 of gain control (see Table 1 for gain settings) GAIN1 4 I Bit 1 of gain control (see Table 1 for gain settings) INN 1 I Negative differential input INP 2 I Positive differential input OUTN 10, 11 O Negative BTL output OUTP 14, 15 O Positive BTL output PGND 6, 12, 13 PVCC ROSC 9, 16 I High-voltage power supply (for output stages) 20 I Connect 120 kΩ resistor to ground to set oscillation frequency. SHUTDOWN 5 I Shutdown terminal (negative logic), TTL compatible, 21-V compliant VCC VCLAMP 24 I Analog high-voltage power supply 7 O Connect 100-nF capacitor to ground to provide reference voltage for H-bridge gates VREF 23 O 5-V internal regulator for control circuitry (connect a 0.1-µF to 1-µF capacitor to ground) 2 Power ground www.ti.com TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 functional block diagram VREF AGND VREF VCC VCLAMP VCC Clamp Reference BSN PVCC + _ Gain Adjust INN Deglitch Logic Gate Drive OUTN _ PGND + _ + Gain Adjust INP BSP + _ PVCC + _ _ + Deglitch Logic Gate Drive OUTP PGND SHUTDOWN SD GAIN1 GAIN0 2 Gain Biases and References Ramp Generator COSC ROSC BYPASS OC Detect{ Start-Up Protection Logic Thermal VCC OK † Short-circuit protection operates only for shorts from the outputs to ground. absolute maximum ratings over operating free-air temperature range (unless otherwise noted)‡ Supply voltage: VCC, PVCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to 21 V Input voltage: SHUTDOWN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to VCC + 0.3 V GAIN0, GAIN1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to 5.5 V INN, INP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to 7 V Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (see Dissipation Rating Table) Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 40°C to 85°C Operating junction temperature range, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 40°C to 150°C Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C } Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. DISSIPATION RATING TABLE PACKAGE PWP TA ≤ 25°C 2.7 W DERATING FACTOR 21.8 mW/°C www.ti.com TA = 70°C 1.7 W TA = 85°C 1.4 W 3 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 recommended operating conditions ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Supply voltage, VCC, PVCC GAIN0, GAIN1, SHUTDOWN† GAIN0, GAIN1, SHUTDOWN† High-level input voltage, VIH Low-level input voltage, VIL MIN MAX 8 18 2 Operating free-air temperature, TA † See Application Information for more information on the characteristics of the SHUTDOWN terminal. – 40 UNIT V V 0.8 V 85 °C electrical characteristics at TA = 25°C, PVCC = VCC = 12 V (unless otherwise noted) ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ PARAMETER TEST CONDITIONS |VOS| Output offset voltage (measured differentially) PSRR Power supply rejection ratio |IIH| High-level input current |IIL| Low-level input current ICC ICC(SD) Supply current Supply current, shutdown mode MIN VI = 0 V, AV = 12 dB PVCC = 11.5 V to 12.5 V PVCC = 12 V, PVCC = 12 V, TYP MAX 50 –75 VI = PVCC UNIT mV dB 1 µA –1 µA 8 15 mA 1 2 µA VI = 0 V operating characteristics, PVCC = VCC = 12 V, TA = 25°C, RL = 8 Ω, Gain = 12 dB (unless otherwise noted) ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ PARAMETER TEST CONDITIONS MIN TYP MAX Output power THD = 0.5%, f = 1 kHz Total harmonic distortion plus noise 1% Maximum output power bandwidth PO = 15 W, THD = 1% f = 20 Hz to 20 kHz BOM kSVR 20 kHz Supply ripple rejection ratio f = 1 kHz, C(BYPASS) = 0.47 µF –70 dB SNR Signal-to-noise ratio PO = 12 W 95 dB C(BYPASS) = 0.47 µF, f = 20 Hz to 22 kHz, No weighting filter used 86 µV(rms) Vn Zi Noise output voltage C(BYPASS) = 0.47 µF, A-weighted filter 7 UNIT PO THD + N f = 20 Hz to 22 kHz, Input impedance W –81 dBV 66 µV(rms) –84 dBV >23 kΩ operating characteristics, PVCC = VCC = 18 V, TA = 25°C, RL = 8 Ω, Gain = 12 dB (unless otherwise noted) ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ PARAMETER TEST CONDITIONS PO THD + N Output power THD = 0.5%, f = 1 kHz Total harmonic distortion plus noise f = 20 Hz to 20 kHz BOM kSVR Maximum output power bandwidth PO = 15 W, THD = 1% Supply ripple rejection ratio f = 1 kHz, CBYPASS = 0.47 µF SNR Signal-to-noise ratio PO = 17 W C(BYPASS) = 0.47 µF, f = 20 Hz to 20 kHz, No weighting filter used Vn Zi 4 Noise output voltage C(BYPASS) = 0.47 µF, A-weighted filter Input impedance www.ti.com f = 20 Hz to 22 kHz, MIN TYP 17 MAX UNIT W 1% 20 kHz 70 dB 102 dB 86 µV(rms) –81 dBV 66 µV(rms) –84 dBV >23 kΩ TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 TYPICAL CHARACTERISTICS Table of Graphs FIGURE Efficiency vs Output power PO ICC Output power IO(sd) Shutdown current 1, 2, 3 4 Supply current vs Supply Su ly voltage 5 vs Output power 7, 8, 9, 10 6 THD+N Total harmonic distortion + noise kSVR Supply voltage rejection ratio vs Frequency 11, 12, 13, 14 15, 16, 17 Gain and phase 18 vs Frequency CMRR Common-mode rejection ratio VIO Input offset voltage 19 vs Common-mode input voltage EFFICIENCY vs OUTPUT POWER EFFICIENCY vs OUTPUT POWER 100 100 90 90 80 80 RL = 8 Ω Speaker 70 Efficiency – % Efficiency – % 70 60 50 40 50 40 30 20 20 VCC = 15 V f = 1 kHz RL = 8 Ω Speaker 60 30 10 20, 21, 22 VCC = 18 V f = 1 kHz 10 0 0 0 3 6 9 12 15 0 2 4 6 8 10 12 PO – Output Power – W PO – Output Power – W Figure 1 Figure 2 www.ti.com 5 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 TYPICAL CHARACTERISTICS EFFICIENCY vs OUTPUT POWER OUTPUT POWER vs SUPPLY VOLTAGE 100 17 90 15 Efficiency – % 70 PO – Output Power – W 80 RL = 8 Ω Speaker 60 50 40 30 13 11 RL = 8 Ω 9 7 20 0 0 1 2 3 VCC = 8 V TO 18 V f = 1 kHz Maximum 1% THD+N 5 VCC = 8 V f = 1 kHz 10 3 4 8 10 PO – Output Power – W 12 Figure 3 18 SHUTDOWN CURRENT vs SUPPLY VOLTAGE 11 5 ICC(SD) – Shutdown Current – µA 10 ICC – Supply Current – mA 16 Figure 4 SUPPLY CURRENT vs SUPPLY VOLTAGE 9 8 7 6 8 10 12 14 16 18 VCC – Supply Voltage – V 4 3 2 1 0 8 10 12 14 VCC – Supply Voltage – V Figure 6 Figure 5 6 14 VCC – Supply Voltage – V www.ti.com 16 18 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 TYPICAL CHARACTERISTICS 10 VCC = 18 V RL = 8 Ω Gain = 12 dB 1 f = 1 kHz 0.1 f = 20 Hz f = 20 kHz 0.01 0.01 0.1 TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER THD+N – Total Harmonic Distortion + Noise – % THD+N – Total Harmonic Distortion + Noise – % TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER 1 10 VCC = 15 V RL = 8 Ω Gain = 12 dB 10 1 f = 20 kHz f = 1 kHz 0.1 f = 20 Hz 0.01 0.01 0.1 PO – Output Power – W Figure 7 f = 1 kHz 0.1 f = 20 kHz f = 20 Hz 0.1 1 TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER THD+N – Total Harmonic Distortion + Noise – % THD+N – Total Harmonic Distortion + Noise – % VCC = 12 V RL = 8 Ω Gain = 12 dB 1 0.01 0.01 10 Figure 8 TOTAL HARMONIC DISTORTION + NOISE vs OUTPUT POWER 10 1 PO – Output Power – W 10 1 f = 1 kHz 0.1 f = 20 Hz f = 20 kHz 0.01 0.01 10 PO – Output Power – W VCC = 8 V RL = 8 Ω Gain = 12 dB 0.1 1 PO – Output Power – W Figure 9 Figure 10 www.ti.com 7 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 TYPICAL CHARACTERISTICS TOTAL HARMONIC DISTORTION + NOISE vs FREQUENCY 1 THD+N – Total Harmonic Distortion + Noise – % THD+N – Total Harmonic Distortion + Noise – % TOTAL HARMONIC DISTORTION + NOISE vs FREQUENCY VCC = 18 V RL = 8 Ω Gain = 12 dB PO = 500 mW PO = 2 W 0.1 PO = 10 W 0.01 20 100 1k 10k 1 VCC = 15 V RL = 8 Ω Gain = 12 dB 0.1 PO = 500 mW PO = 2 W PO = 10 W 0.01 20 100 f – Frequency – Hz f – Frequency – Hz TOTAL HARMONIC DISTORTION + NOISE vs FREQUENCY 1 THD+N – Total Harmonic Distortion + Noise – % THD+N – Total Harmonic Distortion + Noise – % TOTAL HARMONIC DISTORTION + NOISE vs FREQUENCY VCC = 12 V RL = 8 Ω Gain = 12 dB PO = 250 mW 0.1 PO = 1 W PO = 5 W 0.01 100 1k 1 VCC = 8 V RL = 8 Ω Gain = 12 dB PO = 250 mW 0.1 PO = 1 W PO = 5 W 0.01 20 10k 100 1k f – Frequency – Hz f – Frequency – Hz Figure 13 8 10k Figure 12 Figure 11 20 1k Figure 14 www.ti.com 10k TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 TYPICAL CHARACTERISTICS SUPPLY VOLTAGE REJECTION RATIO vs FREQUENCY SUPPLY VOLTAGE REJECTION RATIO vs FREQUENCY –50 kSVR – Supply Voltage Rejection Ratio – dB VDD = 15 V RL = 8 Ω –60 C(Bypass) = 1 µF C(Bypass) = 470 nF –70 C(Bypass) = 100 nF –80 –90 20 100 1k VDD = 12 V RL = 8 Ω –60 C(Bypass) = 470 nF C(Bypass) = 100 nF –70 C(Bypass) = 1 µF –80 –90 20 10k 100 f – Frequency – Hz Figure 15 10k Figure 16 GAIN and PHASE vs FREQUENCY SUPPLY VOLTAGE REJECTION RATIO vs FREQUENCY 30 14 –50 VCC = 8 V RL = 8 Ω 12 C(Bypass) = 1 µF –60 20 Gain 10 0 10 –10 C(Bypass) = 470 nF C(Bypass) = 100 nF –70 Gain – dB kSVR – Supply Voltage Rejection Ratio – dB 1k f – Frequency – Hz 8 –20 Phase 6 –30 Phase – ° kSVR – Supply Voltage Rejection Ratio – dB –50 –40 4 –50 –80 2 –90 20 100 1k 0 10 10k –60 VCC = 8 V RL = 8 Ω Gain = 12 dB 100 –70 1k 10k –80 100k f – Frequency – Hz f – Frequency – Hz Figure 18 Figure 17 www.ti.com 9 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 TYPICAL CHARACTERISTICS COMMON-MODE REJECTION RATIO vs FREQUENCY INPUT OFFSET VOLTAGE vs COMMON-MODE INPUT VOLTAGE 6 VCC = 8 V to 18 V RL = 8 Ω 5 –41 VIO – Input Offset Voltage – mV CMRR – Common-Mode Rejection Ratio – dB –40 –42 –43 –44 –45 VCC = 18 V 4 3 2 1 0 –1 –2 –3 –46 20 100 1k –4 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 10k f – Frequency – Hz VIC – Common-Mode Input Voltage – V Figure 19 Figure 20 INPUT OFFSET VOLTAGE vs COMMON-MODE INPUT VOLTAGE INPUT OFFSET VOLTAGE vs COMMON-MODE INPUT VOLTAGE 6 5 4 VIO – Input Offset Voltage – mV VIO – Input Offset Voltage – mV 5 6 VCC = 12 V 3 2 1 0 –1 –2 4 3 2 1 0 –1 –2 –3 –3 –4 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 –4 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 VIC – Common-Mode Input Voltage – V VIC – Common-Mode Input Voltage – V Figure 21 10 VCC = 8 V Figure 22 www.ti.com TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 APPLICATION INFORMATION eliminating the output filter with the TPA3000D1 This section focuses on how the user can eliminate the output filter with the TPA3000D1. effect on audio The class-D amplifier outputs a pulse-width modulated (PWM) square wave, which is the sum of the switching waveform and the amplified input audio signal. The human ear acts as a band-pass filter such that only the frequencies between approximately 20 Hz and 20 kHz are passed. The switching frequency components are much greater than 20 kHz, so the only signal heard is the amplified input audio signal. traditional class-D modulation scheme The traditional class-D modulation scheme, which is used in the TPA032D0x family, has a differential output where each output is 180 degrees out of phase and changes from ground to the supply voltage, VCC. Therefore, the differential prefiltered output varies between positive and negative VCC, where filtered 50% duty cycle yields 0 V across the load. The traditional class-D modulation scheme with voltage and current waveforms is shown in Figure 23. Note that even at an average of 0 V across the load (50% duty cycle), the current to the load is high, causing high loss, thus causing a high supply current. OUTP OUTN +12 V Differential Voltage Across Load 0V –12 V Current Figure 23. Traditional Class-D Modulation Scheme’s Output Voltage and Current Waveforms Into an Inductive Load With No Input TPA3000D1 modulation scheme The TPA3000D1 uses a modulation scheme that still has each output switching from 0 to the supply voltage. However, OUTP and OUTN are now in phase with each other with no input. The duty cycle of OUTP is greater than 50% and OUTN is less than 50% for positive output voltages. The duty cycle of OUTP is less than 50% and OUTN is greater than 50% for negative output voltages. The voltage across the load sits at 0 V throughout most of the switching period, greatly reducing the switching current, which reduces any I2R losses in the load. www.ti.com 11 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 APPLICATION INFORMATION TPA3000D1 modulation scheme (continued) OUTP OUTN Differential Voltage Across Load Output = 0 V +12 V 0V –12 V Current OUTP OUTN Differential Voltage Output > 0 V +12 V 0V Across Load –12 V Current Figure 24. The TPA3000D1 Output Voltage and Current Waveforms Into an Inductive Load efficiency: filter required with the traditional class-D modulation scheme The main reason that the traditional class-D amplifier needs an output filter is that the switching waveform results in maximum current flow. This causes more loss in the load, which causes lower efficiency. The ripple current is large for the traditional modulation scheme, because the ripple current is proportional to voltage multiplied by the time at that voltage. The differential voltage swing is 2 × VCC, and the time at each voltage is half the period for the traditional modulation scheme. An ideal LC filter is needed to store the ripple current from each half cycle for the next half cycle, while any resistance causes power dissipation. The speaker is both resistive and reactive, whereas an LC filter is almost purely reactive. The TPA3000D1 modulation scheme has very little loss in the load without a filter because the pulses are very short and the change in voltage is VCC instead of 2 × VCC. As the output power increases, the pulses widen, making the ripple current larger. Ripple current could be filtered with an LC filter for increased efficiency, but for most applications the filter is not needed. An LC filter with a cutoff frequency less than the class-D switching frequency allows the switching current to flow through the filter instead of the load. The filter has less resistance than the speaker, which results in less power dissipation, therefore increasing efficiency. 12 www.ti.com TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 APPLICATION INFORMATION effects of applying a square wave into a speaker Audio specialists have advised for years not to apply a square wave to speakers. If the amplitude of the waveform is high enough and the frequency of the square wave is within the bandwidth of the speaker, the square wave could cause the voice coil to jump out of the air gap and/or scar the voice coil. A 250-kHz switching frequency, however, does not significantly move the voice coil, as the cone movement is proportional to 1/f2 for frequencies beyond the audio band. Damage may occur if the voice coil cannot handle the additional heat generated from the high-frequency switching current. The amount of power dissipated in the speaker may be estimated by first considering the overall efficiency of the system. If the on-resistance (rds(on)) of the output transistors is considered to cause the dominant loss in the system, then the maximum theoretical efficiency for the TPA3000D1 with an 8-Ω load is as follows: ǒ Efficiency (theoretical, %) + R ń R ) r L L ds(on) Ǔ 100% + 8ń(8 ) 0.4) 100% + 95.24% (1) The maximum measured output power is approximately 17 W with an 18-V power supply. The total theoretical power supplied (P(total)) for this worst-case condition would therefore be as follows: P (total) + P ńEfficiency + 17 W ń 0.9524 + 17.85 W O (2) The efficiency measured in the lab using an 8-Ω speaker was 89%. The power not accounted for as dissipated across the rds(on) may be calculated by simply subtracting the theoretical power from the measured power: Other losses + P (total) (measured) * P (total) (theoretical) + 19.1 * 17.85 + 1.25 W (3) The quiescent supply current at 18 V is measured to be 9.8 mA. It can be assumed that the quiescent current encapsulates all remaining losses in the device, i.e., biasing and switching losses. It may be assumed that any remaining power is dissipated in the speaker and is calculated as follows: P (dis) + 1.25 W * (18 V 9.8 mA) + 1.07 W (4) Note that these calculations are for the worst-case condition of 17 W delivered to the speaker. Since the 1.07 W is only 6.3% of the power delivered to the speaker, it may be concluded that the amount of power actually dissipated in the speaker is relatively insignificant. Furthermore, this power dissipated is well within the specifications of most loudspeaker drivers in a system, as the power rating is typically selected to handle the power generated from a clipping waveform. when to use an output filter Design the TPA3000D1 without the filter if the traces from amplifier to speaker are short. Powered speakers, where the speaker is in the same enclosure as the amplifier, is a typical application for class-D without a filter. A ferrite bead filter may be used if the design is failing radiated emissions without a filter, or if a frequency sensitive circuit is operating higher than 1 MHz. The ferrite filter reduces EMI around 1 MHz and higher (FCC and CE only test radiated emissions greater than 30 MHz). When selecting a ferrite bead, choose one with high impedance at high frequencies, but very low impedance at low frequencies. Use a LC output filter if there are low frequency (<1 MHz) EMI sensitive circuits and/or there are long wires from the amplifier to the speaker. www.ti.com 13 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 APPLICATION INFORMATION when to use an output filter (continued) 15 µH OUTP 0.22 µF 15 µH 1 µF OUTN 0.22 µF Figure 25. Typical LC Output Filter, Cutoff Frequency of 41 kHz Ferrite Chip Bead OUTP 1 nF Ferrite Chip Bead OUTN 1 nF Figure 26. Typical Ferrite Chip Bead Filter (Chip bead example: Fair-Rite 2512067007Y3) gain setting via GAIN0 and GAIN1 inputs The gain of the TPA3000D1 is set by two input terminals, GAIN0 and GAIN1. The gains listed in Table 1 are realized by changing the taps on the input resistors inside the amplifier. This causes the input impedance (Zi) to be dependent on the gain setting. The actual gain settings are controlled by ratios of resistors, so the actual gain distribution from part-to-part is quite good. However, the input impedance may shift by 30% due to shifts in the actual resistance of the input resistors. For design purposes, the input network (discussed in the next section) should be designed assuming an input impedance of 23 kΩ, which is the absolute minimum input impedance of the TPA3000D1. At the lower gain settings, the input impedance could increase as high as 313 kΩ. Table 1. Gain Settings 14 AMPLIFIER GAIN (dB) INPUT IMPEDANCE (kΩ) TYP TYP 12 241 1 18 168 0 23.5 104 1 36 33 GAIN0 GAIN1 0 0 0 1 1 www.ti.com TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 APPLICATION INFORMATION 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. Zf Ci Input Signal Zi IN The –3-dB frequency can be calculated using equation 5. f+ 1 2p Z iC i (5) input capacitor, Ci In the typical application an input capacitor (Ci) is required to allow the amplifier to bias the input signal to the proper dc level for optimum operation. In this case, Ci and the input impedance of the amplifier (Zi) form a high-pass filter with the corner frequency determined in equation 6. –3 dB fc + (6) 1 2 p Zi Ci fc The value of Ci is important, as it directly affects the bass (low frequency) performance of the circuit. Consider the example where Zi is 241 kΩ and the specification calls for a flat bass response down to 20 Hz. Equation 6 is reconfigured as equation 7. Ci + 1 2p Z i f c (7) In this example, Ci is 33 nF, so one would likely choose a value of 0.1 µF as this value is commonly used. If the gain is known and will be constant, use Zi from Table 1 to calculate Ci. A further consideration for this capacitor is the leakage path from the input source through the input network (Ci) and the feedback network to the load. This leakage current creates a dc offset voltage at the input to the amplifier that reduces useful headroom, especially in high gain applications. For this reason a low-leakage tantalum or ceramic capacitor is the best choice. When polarized capacitors are used, the positive side of the capacitor should face the amplifier input in most applications as the dc level there is held at 2.5 V, which is likely higher than the source dc level. Note that it is important to confirm the capacitor polarity in the application. www.ti.com 15 TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 APPLICATION INFORMATION power supply decoupling, CS The TPA3000D1 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. For higher frequency transients, spikes, or digital hash on the line, a good low equivalent-series-resistance (ESR) ceramic capacitor, typically 0.1 µF placed as close as possible to the device VCC lead works best. For filtering lower-frequency noise signals, a larger aluminum electrolytic capacitor of 10 µF or greater placed near the audio power amplifier is recommended. BSN and BSP capacitors The full H-bridge output stage uses only NMOS transistors. It therefore requires bootstrap capacitors for the high side of each output to turn on correctly. A 10-nF ceramic capacitor, rated for at least 25 V, must be connected from each output to its corresponding bootstrap input. Specifically, one 10-nF capacitor must be connected from OUTP to BSP, and one 10-nF capacitor must be connected from OUTN to BSN. (See the evaluation circuit diagram at the end of this data sheet.) VCLAMP capacitors To ensure that the maximum gate-to-source voltage for the NMOS output transistors is not exceeded, an internal regulator clamps the gate voltage. A 0.1-µF capacitor must be connected from VCLAMP (pin 7) to ground and must be rated for at least 25 V. The voltage at VCLAMP (pin 7) varies with VCC and may not be used for powering any other circuitry. midrail bypass capacitor, CBYPASS The midrail bypass capacitor (CBYPASS) is the most critical capacitor and serves several important functions. During start-up or recovery from shutdown mode, CBYPASS determines the rate at which the amplifier starts up. The second function is to reduce noise produced by the power supply caused by coupling into the output drive signal. This noise is from the midrail generation circuit internal to the amplifier, which appears as degraded PSRR and THD+N. Bypass capacitor (CBYPASS) values of 0.47-µF to 1-µF ceramic or tantalum low-ESR capacitors are recommended for the best THD noise, and depop performance. VREF decoupling capacitor The VREF terminal (pin 23) is the output of an internally-generated 5-V supply, used for the oscillator and gain setting logic. It requires a 0.1-µF to 1-µF capacitor to ground to keep the regulator stable. The regulator may not be used to power any additional circuitry. differential input The differential input stage of the amplifier cancels any noise that appears on both input lines of the channel. To use the TPA3000D1 EVM with a differential source, connect the positive lead of the audio source to the INP input and the negative lead from the audio source to the INN input. To use the TPA3000D1 with a single-ended source, ac ground the INN input through a capacitor and apply the audio single to the input. In a single-ended input application, the INN input should be ac-grounded at the audio source instead of at the device input for best noise performance. 16 www.ti.com TPA3000D1 SLOS379A – SEPTEMBER 2001 – REVISED JANUARY 2002 ,APPLICATION INFORMATION SHUTDOWN operation The TPA3000D1 employs a shutdown mode of operation designed to reduce supply current (ICC) to the absolute minimum level during periods of nonuse for battery-power conservation. The SHUTDOWN input terminal should be held high during normal operation when the amplifier is in use. Pulling SHUTDOWN low causes the outputs to mute and the amplifier to enter a low-current state, ICC(SD) = 1 µA. SHUTDOWN should never be left unconnected, because amplifier operation would be unpredictable. Ideally, the device should be held in shutdown when the system powers up and brought out of shutdown once any digital circuitry has settled. However, if SHUTDOWN is to be left unused or if the device is to be powered up with SHUTDOWN held high, the circuit below should be used. VCC (or SHUTDOWN Control Signal, TTL Compatible) R(SD) 120 kΩ SHUTDOWN Pin 23 CSD 0.1 µF The values for RSD and CSD should be chosen for a time constant (τ = RSDCSD) of at least 10 ms for proper operation. The maximum output current of the SHUTDOWN control signal source must not be exceeded. using low-ESR capacitors Low-ESR capacitors are recommended throughout this application section. 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. www.ti.com 17 MECHANICAL DATA MHTS001D – JANUARY 1995 – REVISED MAY 1999 MECHANICAL DATA PWP (R-PDSO-G**) PowerPAD PLASTIC SMALL-OUTLINE 20 PINS SHOWN 0,30 0,19 0,65 20 0,10 M 11 Thermal Pad (See Note D) 4,50 4,30 0,15 NOM 6,60 6,20 Gage Plane 1 10 0,25 A 0°–ā8° 0,75 0,50 Seating Plane 0,15 0,05 1,20 MAX PINS ** 0,10 14 16 20 24 28 A MAX 5,10 5,10 6,60 7,90 9,80 A MIN 4,90 4,90 6,40 7,70 9,60 DIM 4073225/F 10/98 NOTES: A. B. C. D. All linear dimensions are in millimeters. This drawing is subject to change without notice. Body dimensions do not include mold flash or protrusions. The package thermal performance may be enhanced by bonding the thermal pad to an external thermal plane. This pad is electrically and thermally connected to the backside of the die and possibly selected leads. E. Falls within JEDEC MO-153 PowerPAD is a trademark of Texas Instruments. 18 www.ti.com IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. 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