PW TPA2000D1 GQC www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 2-W FILTERLESS MONO CLASS-D AUDIO POWER AMPLIFIER FEATURES • • • • • • • Modulation Scheme Optimized to Operate Without a Filter 4 mm × 4 mm MicroStar Junior BGA and TSSOP Package Options 2 W Into a 4-Ω Speaker (THD+N<1%) <0.2% THD+N at 1.5 W, 1 kHz, Into a 4-Ω Load Extremely Efficient Third Generation 5-V Class-D Technology: – Low-Supply Current (No Filter): 4 mA – Low-Supply Current (Filter): 7.5 mA – Low-Shutdown Current: 0.05 µA – Low-Noise Floor: 40 µVRMS (No-Weighting Filter) – Maximum Efficiency Into 8 Ω, 75 - 85 % – 4 Internal Gain Settings: 6 to 23.5 dB – PSRR: -77 dB Integrated Depop Circuitry Short-Circuit Protection (Short to Battery, Ground, and Load) APPLICATIONS • High-Efficiency For Extended Battery Run Time PW PACKAGE (TOP VIEW) INP INN SHUTDOWN GAIN0 GAIN1 PVDD OUTP PGND 1 2 3 4 5 6 7 8 BYPASS AGND COSC ROSC VDD PVDD OUTN PGND 16 15 14 13 12 11 10 9 MicroStar Junior (GQC) Package (TOP VIEW) INP AGND BYPASS A2 INN SHUTDOWN GAIN0 GAIN1 PVDD PVDD OUTP A6 A1 A7 B1 B7 C1 C7 D1 D7 E1 E7 F1 F7 G1 G7 NC COSC ROSC VDD PVDD PVDD OUTN PGND (SIDE VIEW) NC – No internal connection, still requires a pad for the ball. NOTE: The shaded terminals are used for thermal connections to the ground plane. DESCRIPTION The TPA2000D1 is a 2-W mono bridge-tied-load (BTL) class-D amplifier designed to drive a speaker with at least 4-Ω impedance. The amplifier uses TI's third generation modulation technique, which results in improved efficiency and SNR. It also allows the device to be connected directly to the speaker without the use of the LC output filter commonly associated with class-D amplifiers (this results in EMI that must be shielded at the system level). These features make the device ideal for use in devices where high efficiency is needed to extend battery run time. 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 6, 12, 18, and 23.5 dB. The differential input terminals are high-impedance CMOS inputs, and can be used as summing nodes. The class-D BTL amplifier includes depop circuitry to reduce the amount of turnon pop at power up and when cycling SHUTDOWN. The TPA2000D1 is available in the 16-pin TSSOP and MicroStar Junior™ BGA packages that drive 2 W of continuous output power into a 4-Ω load. TPA2000D1 operates over an ambient temperature range of -40°C to 85°C. 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. MicroStar Junior 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. Copyright © 2000–2004, Texas Instruments Incorporated TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 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. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. AVAILABLE OPTIONS PACKAGED DEVICES TA 40°C to 85°C (1) (2) TSSOP (PW) (1) GQC (2) TPA2000D1PW TPA2000D1GQCR The PW package is available taped and reeled. To order a taped and reeled part, add the suffix R to the part number (e.g., TPA2000D1PWR). The GQC package is only available taped and reeled. FUNCTIONAL BLOCK DIAGRAM VDD AGND VDD Gain Adjust INN PVDD _ + _ Deglitch Logic Gate Drive OUTN + _ + PGND + _ PVDD + Gain Adjust INP _ _ + Deglitch Logic Gate Drive OUTP PGND SHUTDOWN GAIN1 GAIN0 COSC ROSC BYPASS 2 Gain 2 Biases and References Ramp Generator Start-Up Protection Logic Thermal VDD ok OC Detect TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 TERMINAL FUNCTIONS TERMINAL NAME NO. I/O DESCRIPTION GQC PW A3 - A5, B2 - B6 C2 - C6 D2 - D4 15 I Analog ground BYPASS A6 16 I Connect capacitor to ground for BYPASS voltage filtering. COSC B7 14 I Connect capacitor to ground to set oscillation frequency. GAIN0 C1 4 I Bit 0 of gain control (TTL logic level) GAIN1 D1 5 I Bit 1 of gain control (TTL logic level) INN A1 2 I Negative differential input INP A2 1 I Positive differential input OUTN G7 10 O Negative BTL output OUTP G1 7 O Positive BTL output PGND D5, D6 E2 - E6 F2 - F6 G2 - G6 8, 9 I High-current grounds PVDD E1, E7, F1, F7 6, 11 I High-current power supplies ROSC C7 13 I Connect resistor to ground to set oscillation frequency. SHUTDOWN B1 3 I Places the amplifier in shutdown mode if a TTL logic low is placed on this terminal, and normal operation if a TTL logic high is placed on this terminal. VDD D7 12 I Analog power supply AGND ABSOLUTE MAXIMUM RATINGS over operating free-air temperature range (unless otherwise noted) (1) UNITS Supply voltage VDD, PVDD -0.3 V to 5.5 V Input voltage, VI -0.3 V to VDD +0.3 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 (1) 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 TA ≤ 25°C DERATING FACTOR TA = 70°C TA = 85°C PW 774 mW 6.19 mW/°C 495 mW 402 mW GQC 2.61 W 20.9 mW/°C 1.67 W 1.36 W 3 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 RECOMMENDED OPERATING CONDITIONS MIN MAX 2.7 5.5 UNIT VDD, PVDD Supply voltage VIH High-level input voltage GAIN0, GAIN1, SHUTDOWN VIL Low-level input voltage GAIN0, GAIN1, SHUTDOWN 0.7 V fs Switching frequency 200 300 kHz TA Operating free-air temperature -40 85 °C 2 V V ELECTRICAL CHARACTERISTICS at specified free-air temperature, PVDD = VDD = 5 V, TA = 25°C (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT 25 mV |VOS| Output offset voltage (measured differentially) VI = 0 V, PSRR Power supply rejection ratio PVDD = 4.9 V to 5.1 V |IIH| High-level input current PVDD = 5.5, VI = PVDD 1 µA |IIL| Low-level input current PVDD = 5.5, VI = 0 V 1 µA IDD Supply current, no filter (with or without speaker load) 4 6 mA IDD(SD) Supply current, shutdown mode 0.05 20 µA MAX UNIT AV = any gain -77 GAIN0, GAIN1, SHUTDOWN = 0 V dB OPERATING CHARACTERISTICS PVDD = VDD = 5 V, TA = 25°C, RL = 4 Ω, gain = 6 dB (unless otherwise noted) PARAMETER TEST CONDITIONS PO Output power THD = 1%, f = 1 kHz, THD + N Total harmonic distortion plus noise PO = 1.5 W, f = 20 Hz to 20 kHz kSVR Supply ripple rejection ratio f = 1 kHz, CBYP = 1 µF SNR Signal-to-noise ratio Vn Output noise voltage (no-noise weighting filter) Zi Input impedance CBYP = 1 µF, MIN TYP 2 W <0.2% -67 dB 95 dB 40 µV(rms) >15 kΩ f = < 10 Hz to 22 kHz ELECTRICAL CHARACTERISTICS at specified free-air temperature, PVDD = VDD = 3.3 V, TA = 25°C (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT |VOS| Output offset voltage (measured differentially) VI = 0 V PSRR Power supply rejection ratio PVDD = 3.2 V to 3.4 V |IIH| High-level input current PVDD = 3.3 VI = PVDD 1 µA |IIL| Low-level input current PVDD = 3.3 VI = 0 V 1 µA IDD Supply current, no filter (with or without speaker load) 4 6 mA IDD(SD) Supply current, shutdown mode 0.05 20 µA 4 AV = any gain 25 -61 mV dB TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 OPERATING CHARACTERISTICS PVDD = VDD = 3.3 V, TA = 25°C, RL = 4 Ω, gain = 6 dB (unless otherwise noted) PARAMETER TEST CONDITIONS MIN PO Output power THD = 1%, f = 1 kHz THD + N Total harmonic distortion plus noise PO = 55 mW, f = 20 Hz to 20 kHz kSVR Supply ripple rejection ratio f = 1 kHz, CBYP = 1 µF SNR Signal-to-noise ratio Vn Output noise voltage (no-noise weighting filter) Zi Input impedance CBYP= 1 µF, TYP 850 f = <10 Hz to 22 kHz MAX UNIT mW <0.2% -61 dB 93 dB 40 µV(rms) >15 kΩ Table 1. GAIN SETTINGS AMPLIFIER GAIN (dB) INPUT IMPEDANCE (kΩ) TYP TYP 6 104 12 74 0 18 44 1 23.5 24 GAIN1 GAIN0 0 0 0 1 1 1 5 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 TYPICAL CHARACTERISTICS TABLE OF GRAPHS FIGURE η Efficiency vs Output power 1 FFT at 1.5-W output power vs Frequency 2 THD+N Total harmonic distortion plus noise k(SRR) Supply ripple rejection ratio vs Output power 3, 4, 5 vs Frequency 6, 7 vs Frequency 8 TEST SETUP FOR GRAPHS The THD+N measurements shown do not use an LC output filter, but do use a 100-Ω, 0.047-µF RC low-pass filter with a cutoff frequency of ~30 kHz before the audio analyzer so the switching frequency does not dominate the measurement. This is done to ensure that the THD+N measured is just the audible THD+N. The THD+N measurements are shown at the highest gain for worst case. The efficiency was measured with no filters, and a 3-Ω, 4-Ω, or 8-Ω resistor in series with a 33-µH inductor as the load. EFFICIENCY vs OUTPUT POWER 100 RL = 8 Ω, 33 µH RL = 4 Ω, 33 µH 90 80 RL = 3 Ω, 33 µH Efficiency − % 70 60 50 Class-AB, RL = 4 Ω 40 30 20 10 0 0 0.5 2.5 1 1.5 2 PO − Output Power − W Figure 1. 6 3 3.5 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 TYPICAL CHARACTERISTICS (continued) FFT AT 1.5-W OUTPUT POWER vs FREQUENCY +10 VDD = 5 V, RL = 4 Ω, f = 1 kHz, PO = 1.5 W −10 Power − VdB −30 −50 −70 −90 −110 −130 −150 0 4k 8k 12 k f − Frequency − Hz 16 k 20 k 24 k Figure 2. TOTAL HARMONIC DISTORTION PLUS NOISE vs OUTPUT POWER 10 2 THD+N − Total Harmonic Distortion Plus Noise − % THD+N − Total Harmonic Distortion Plus Noise − % TOTAL HARMONIC DISTORTION PLUS NOISE vs OUTPUT POWER VDD = 5 V, Gain = 23.5, RL = 3 Ω 1 f = 1 kHz 0.2 0.1 f = 20 Hz 0.02 0.01 0.01 10 m f = 20 kHz 10 2 VDD = 5 V, Gain = 23.5, RL = 4 Ω 1 f = 1 kHz 0.2 0.1 f = 20 Hz 0.02 0.01 f = 20 kHz 0.001 10 m PO − Output Power − W 100 m 200 m PO − Output Power − W Figure 3. Figure 4. 100 m 200 m 1 3 1 3 7 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 TYPICAL CHARACTERISTICS (continued) THD+N − Total Harmonic Distortion Plus Noise − % 10 VDD = 5 V, Gain = 23.5, RL = 8 Ω 2 1 0.2 f = 1 kHz 0.1 f = 20 Hz 0.02 0.01 f = 20 kHz 0.001 10 m 100 m 200 m 1 3 1 VDD = 5 V, f = 1 kHz, RL = 4 Ω 0.2 0.1 PO = 1.5 W 0.02 0.01 PO = 0.75 W PO = 2 W 0.001 20 100 200 1k 2k 10 k PO − Output Power − W f − Frequency − Hz Figure 5. Figure 6. TOTAL HARMONIC DISTORTION PLUS NOISE vs FREQUENCY SUPPLY RIPPLE REJECTION RATIO vs FREQUENCY 1 20 k −40 VDD = 5 V, f = 1 kHz, RL = 8 Ω 0.2 PO = 0.1 W 0.1 0.02 0.01 PO = 1 W PO = 0.5 W 0.001 −45 −50 −55 −60 −65 −70 −75 −80 20 8 TOTAL HARMONIC DISTORTION PLUS NOISE vs FREQUENCY K(SVR) − Supply Ripple Rejection Ratio − dB THD+N − Total Harmonic Distortion Plus Noise − % THD+N − Total Harmonic Distortion Plus Noise − % TOTAL HARMONIC DISTORTION PLUS NOISE vs OUTPUT POWER 100 200 1k 2k 10 k 20 k 10 100 200 1k 2k f − Frequency − Hz f − Frequency −Hz Figure 7. Figure 8. 10 k 20 k TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 APPLICATION INFORMATION ELIMINATING THE OUTPUT FILTER WITH THE TPA2000D1 This section explains why the user can eliminate the output filter with the TPA2000D1. 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 TPA005Dxx family, has a differential output where each output is 180 degrees out of phase and changes from ground to the supply voltage, VDD. Therefore, the differential prefiltered output varies between positive and negative VDD, 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 9. Even at an average of 0 V across the load (50% duty cycle), the current to the load is high, causing high loss, and a high supply current. OUTP OUTN +5 V Differential Voltage Across Load OV –5 V Current Figure 9. Traditional Class-D Modulation Scheme Output Voltage and Current Waveforms Into an Inductive Load With No Input TPA2000D1 MODULATION SCHEME The TPA2000D1 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 voltages. The duty cycle of OUTP is less than 50% and OUTN is greater than 50% for negative 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. 9 TPA2000D1 SLOS328F – JUNE 2000 – REVISED MARCH 2004 www.ti.com APPLICATION INFORMATION (continued) OUTP OUTN Differential Voltage Across Load Output = 0 V +5 V 0V –5 V Current OUTP OUTN Differential +5 V Voltage Across 0V Load Output > 0 V –5 V Current Figure 10. The TPA2000D1 Output Voltage and Current Waveforms Into an Inductive Load EFFICIENCY: WHY YOU MUST USE A FILTER 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 × VDD 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 TPA2000D1 modulation scheme has little loss in the load without a filter because the pulses are short and the change in voltage is VDD instead of 2 × VDD. 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 that results in less power dissipated, which increases efficiency. 10 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 APPLICATION INFORMATION (continued) EFFECTS OF APPLYING A SQUARE WAVE INTO A SPEAKER Audio specialists advise 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, is not significant because the speaker cone movement is proportional to 1/f2 for frequencies beyond the audio band. Therefore, the amount of cone movement at the switching frequency is very small. However, damage could occur to the speaker if the voice coil is not designed to handle the additional power. To size the speaker for added power, the ripple current dissipated in the load needs to be calculated by subtracting the theoretical supplied power (PSUP THEORETICAL) from the actual supply power (PSUP) at maximum output power (POUT). The switching power dissipated in the speaker is the inverse of the measured efficiency (ηMEASURED) minus the theoretical efficiency (ηTHEORETICAL) all multiplied by POUT. PSPKR = PSUP – PSUP THEORETICAL (at max output power) (1) PSPKR = POUT(PSUP / POUT – PSUP THEORETICAL / POUT) (at max output power) (2) PSPKR = POUT(1/ηMEASURED – 1/ηTHEORETICAL) (at max output power) (3) The maximum efficiency of the TPA2000D1 with an 8-Ω load is 85%. Using Equation 3 with the efficiency at maximum power (78%), we see that there is an additional 106 mW dissipated in the speaker. The added power dissipated in the speaker is not an issue as long as it is taken into account when choosing the speaker. WHEN TO USE AN OUTPUT FILTER Design the TPA2000D1 without the filter if the traces from amplifier to speaker are short. The TPA2000D1 passed FCC and CE radiated emissions with no shielding with speaker wires eight inches long or less. Notebook PCs and powered speakers where the speaker is in the same enclosure as the amplifier are good applications for class-D without a filter. A ferrite bead filter (shown in Figure 11) can often be used if the design is failing radiated emissions without a filter, and the frequency sensitive circuit is greater than 1 MHz. This is good for circuits that just have to pass FCC and CE because FCC and CE only test radiated emissions greater than 30 MHz. If choosing a ferrite bead, choose one with high impedance at high frequencies, but low impedance at low frequencies. Use an LC output filter if there are low frequency (<1 MHz) EMI sensitive circuits and/or there are long leads from amplifier to speaker. The LC output filter is shown in Figure 11. • L1 = L2 = 22 µH (DCR = 110 mΩ, part number = SCD0703T-220 M-S, manufacturer = GCI) • C1 = C2 = 1 µF The ferrite filter is shown in Figure 11, where L is a ferrite bead. • L1 = L2 = ferrite bead (part number = MPZ1608S221, manufacturer = TDK) • C1 = C2 = 1 nF L1 OUT+ C1 OUT– L2 C2 Figure 11. Class-D Output Filter 11 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 APPLICATION INFORMATION (continued) GAIN SETTING VIA GAIN0 AND GAIN1 INPUTS The gain of the TPA2000D1 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 can shift by up to 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 20 kΩ, which is the absolute minimum input impedance of the TPA2000D1. At the higher gain settings, the input impedance can increase as high as 115 kΩ. Table 2. GAIN SETTINGS AMPLIFIER GAIN (dB) INPUT IMPEDANCE (kΩ) TYP TYP 6 104 1 12 74 0 18 44 1 23.5 24 GAIN1 GAIN0 0 0 0 1 1 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 IN The -3-dB frequency can be calculated using Equation 4. 1 f 3 dB 2 CiZ i 12 Zi (4) TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 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 5. −3 dB fc 1 2 Zi C i fc (5) The value of Ci is important because it directly affects the bass (low frequency) performance of the circuit. Consider the example where Zi is 20 kΩ and the specification calls for a flat bass response down to 80 Hz. Equation 5 is reconfigured as Equation 6. 1 Ci 2 Z i f c (6) In this example, Ci is 0.1 µF, so one would likely choose a value in the range of 0.1 µF to 1 µF. If the gain is known and 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 VDD/2, which is likely higher than the source dc level. It is important to confirm the capacitor polarity in the application. Ci must be 10 times smaller than the bypass capacitor to reduce clicking and popping noise from power on/off and entering and leaving shutdown. After sizing Ci for a given cutoff frequency, size the bypass capacitor to 10 times that of the input capacitor. C C i BYP 10 (7) POWER SUPPLY DECOUPLING, CS The TPA2000D1 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 VDD 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. MIDRAIL BYPASS CAPACITOR, CBYP The midrail bypass capacitor (CBYP) is the most critical capacitor and serves several important functions. During start-up or recovery from shutdown mode, CBYP 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 (CBYP) values of 0.47-µF to 1-µF ceramic or tantalum low-ESR capacitors are recommended for the best THD and noise performance. 13 TPA2000D1 SLOS328F – JUNE 2000 – REVISED MARCH 2004 www.ti.com Increasing the bypass capacitor reduces clicking and popping noise from power on/off and entering and leaving shutdown. To have minimal pop, CBYP should be 10 times larger than Ci. C BYP 10 C i (8) DIFFERENTIAL INPUT The differential input stage of the amplifier cancels any noise that appears on both input lines of the channel. To use the TPA2000D1 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 TPA2000D1 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. SHUTDOWN MODES The TPA2000D1 employs a shutdown mode of operation designed to reduce supply current (IDD) 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, IDD(SD) = 1 µA. SHUTDOWN should never be left unconnected because amplifier operation would be unpredictable. 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. 14 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 SWITCHING FREQUENCY The switching frequency is determined using the values of the components connected to ROSC (pin 13) and COSC (pin 14) and are calculated using Equation 9. 6.6 fs ROSC COSC (9) The switching frequency was chosen to be centered on 250 kHz. This frequency represents the optimization of audio fidelity due to oversampling and the maximization of efficiency by minimizing the switching losses of the amplifier. The recommended values are a resistance of 120 kΩ and a capacitance of 220 pF. Using these component values, the amplifier operates properly by using 5% tolerance resistors and 10% tolerance capacitors. The tolerance of the components can be changed as long as the switching frequency remains between 200 kHz and 300 kHz. Within this range, the internal circuitry of the device provides stable operation. APPLICATION CIRCUIT TPA2000D1 C2 Audio Input– C3 Audio Input+ 1 µF 1 µF To System Controller 1 INP 2 BYPASS INN AGND 16 15 C7 1 µF C1 3 SHUTDOWN COSC 14 Gain Select 4 GAIN0 13 220 pF Gain Select 5 6 VDD C8 10 µF C4 1 µF 7 8 GAIN1 ROSC VDD PVDD PVDD OUTP OUTN PGND PGND 12 11 R1 120 kΩ C6 1 µF VDD OUT– 10 9 VDD C5 1 µF OUT+ Table 3. TPA2000D1 APPLICATION CIRCUIT BILL OF MATERIALS SIZE QUANTITY MANUFACTURER C1 REFERENCE Capacitor, ceramic, 220 pF, ±10%, XICON, 50 V DESCRIPTION 0805 1 Mouser 140-CC501B221K PART NUMBER C2 - C7 Capacitor, ceramic, 1 µF, +80%/-20%, Y5V, 16 V 0805 6 Murata GRM40-Y5V105Z16 C8 Capacitor, ceramic, 10 µF, +80%/-20%, Y5V, 16 V 1210 1 Murata GRM235-Y5V106Z16 R1 Resistor, chip, 120 kΩ, 1/10 W, 5%, XICON 0805 1 Mouser 260-120K U1 IC, TPA2000D1, audio power amplifier, 2-W, single channel, class-D 24-pin TSSOP 1 TI TPA2000D1PW 15 TPA2000D1 www.ti.com SLOS328F – JUNE 2000 – REVISED MARCH 2004 LOW SUPPLY VOLTAGE POP The TPA2000D1 pops when coming out of shutdown at low supply voltages (3.3 V and less) when using the application schematic shown above. The pops occur because the common-mode input range is worse at the lower supply voltages. At low supply voltages, the inputs are not within the common-mode input range when coming out of shutdown. The outputs develop an offset voltage until the inputs settle within the common-mode input range. This causes a pop. Figure 12 shows 1-MΩ resistors added to form voltage dividers. The voltage dividers bias the inputs to VDD/2 that keeps the pop low at turn on and when coming out of shutdown. The resistors should be 1% tolerance to ensure the offset voltage is not increased. VDD 1 M + 1 M Audio In 1 M INP INN TPA2000D1 − 1 M VDD Figure 12. Voltage Dividers 16 PACKAGE OPTION ADDENDUM www.ti.com 18-Jul-2006 PACKAGING INFORMATION Orderable Device Status (1) TPA2000D1GQCR ACTIVE BGA MI CROSTA R JUNI OR TPA2000D1PW ACTIVE TPA2000D1PWG4 Package Type Package Drawing Pins Package Eco Plan (2) Qty Lead/Ball Finish MSL Peak Temp (3) Level-2A-235C-4 WKS GQC 48 2500 TBD SNPB TSSOP PW 16 90 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM ACTIVE TSSOP PW 16 90 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM TPA2000D1PWR ACTIVE TSSOP PW 16 2000 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM TPA2000D1PWRG4 ACTIVE TSSOP PW 16 2000 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 1 MECHANICAL DATA MPLG008D – APRIL 2000 – REVISED FEBRUARY 2002 GQC (S-PBGA-N48) PLASTIC BALL GRID ARRAY 4,10 3,90 SQ 3,00 TYP 0,50 G F 0,50 E D 3,00 TYP C B A 1 A1 Corner 2 3 4 5 6 7 Bottom View 0,77 0,71 1,00 MAX Seating Plane 0,35 0,25 0,25 0,05 M 0,08 0,15 4200460/E 01/02 NOTES: A. B. C. D. All linear dimensions are in millimeters. This drawing is subject to change without notice. MicroStar Junior BGA configuration Falls within JEDEC MO-225 MicroStar Junior is a trademark of Texas Instruments. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 1 MECHANICAL DATA MTSS001C – JANUARY 1995 – REVISED FEBRUARY 1999 PW (R-PDSO-G**) PLASTIC SMALL-OUTLINE PACKAGE 14 PINS SHOWN 0,30 0,19 0,65 14 0,10 M 8 0,15 NOM 4,50 4,30 6,60 6,20 Gage Plane 0,25 1 7 0°– 8° A 0,75 0,50 Seating Plane 0,15 0,05 1,20 MAX PINS ** 0,10 8 14 16 20 24 28 A MAX 3,10 5,10 5,10 6,60 7,90 9,80 A MIN 2,90 4,90 4,90 6,40 7,70 9,60 DIM 4040064/F 01/97 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 protrusion not to exceed 0,15. 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