Texas Instruments APA100 Manual de usuario Pagina 1

APA100100−W Analog Input Class-D AmplifierTPA2001D1/TAS5111August 2004 Audio Power AmplifiersUser’s GuideSLOU170

EVM Basic Function/Block Diagram1-4Figure 1−2. APA100 EVM Block DiagramAudio InputGain(TLV2464)FeedbackandIntegrator(TLV2464)AudioOutputAnalog InputCl

2-1PCB Design PCB DesignThis chapter gives layout guidelines for the APA100 reference design.Topic Page2.1 PCB Layout 2-2. . . . . . . . . . . . . . .

PCB Layout2-22.1 PCB LayoutThe critical part of the design lies particularly in the layout process. The EVMlayout should be followed exactly for optim

PCB Layout2-3PCB DesignFigure 2−2. APA100 Split Plane Bottom Layout2.1.2 H-Bridge LayoutThe H-bridge is laid out based on recommendations from the TAS

PCB Layout2-43) Use a split ground plane to keep high switching ground currents from theoperational amplifier circuitry.4) Place decoupling capacitors

PCB Layout2-5PCB DesignFigure 2−4. Bottom Copper and SilkscreenFigure 2−5. Drill DrawingSIZE QTY STM PLTD18 4 PLTD28 40 PLTD42 21 PLTD89 3 PLTD116 6 P

Bill of Materials2-62.2 Bill of MaterialsTable 2−1.Parts ListReference Qty Value Manufacturer Part Number DescriptionC23,24 2 22 pF TDK C1608C0G1H220J

Schematic2-7PCB Design2.3 Schematic

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3-1EVM Operation EVM OperationThis chapter covers in detail the operation of the APA100 EVM to guide theuser in evaluating the audio power amplifier a

IMPORTANT NOTICETexas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications,enhancements, improvemen

Quick Start3-23.1 Quick StartFollow these steps to use the APA100 EVM.APA100 audio input connection can be made via a phono jack (J1), or by sol-derin

Power−Up/Down Sequence3-3EVM OperationPower Up6) Press and hold the RESET button (S1)7) Verify correct voltage and input polarity, and set the externa

Changing the Gain3-43.5 Changing the GainThe APA100 EVM is set with a gain of 31.4 dB, but can be adjusted. Thefront-end has a gain of 4.4 dB (−1.667

4-1Technical Information Technical InformationThis chapter goes into the details of the design of the 100-W amplifier. Thedesign comprises the modulat

Feedback System Design4-24.1 Feedback System DesignThe APA100 EVM uses feedback to lower distortion, increase supply ripplerejection, and make the gai

Feedback System Design4-3Technical Informationoperational amplifier (R22, R23, C20, C23, and C24) was eventually reducedfrom 400 kHz to 252 kHz to opt

Feedback System Design4-4Figure 4−3. Open− and Closed−Loop Frequency Response With TPA2001D1 Pole and Canceling ZeroOpen Loop GainClosed Loop GainFc =

Feedback System Design4-5Technical InformationThe closed−loop gain is set to 27 dB to allow enough gain from the 3−V signalto the A+ voltage range. Th

Feedback System Design4-6Instead of calculating the bandwidth, PSPICE was used with a linearizedcircuit (see Figure 4−5) to simulate and adjust the co

TPA2001D1 (Class-D Modulator)4-7Technical InformationFigure 4−6. PSPICE Simulation of Open−Loop Responsef − Frequency − HzTAS5111Output (dB)Integrator

Information About Cautions and Warningsiii PrefaceRead This FirstAbout This ManualThis user’s guide describes the characteristics, operation, and the

TPA2001D1 (Class-D Modulator)4-8Figure 4−7. TPA2001D1 Block Diagram_+GainAdj._++_cmvGainAdj.Rs2Rs1_+_+Cint2Cint1_+DeglitchLogicDeglitchLogicComparator

TAS5111 (H-Bridge)4-9Technical InformationFor more information concerning the TPA2001D1 operation and modulationscheme, see the TPA2001D1 data sheet h

LC Filter4-104.5 LC FilterThe LC filter serves two purposes in this design.1) Reduces EMI2) Enables overcurrent (OC) protection.The outputs of the TAS

Thermal4-11Technical Information4.6 ThermalThe APA100 thermal issues lie with the TAS5111. The following thermalcalculations and tables are taken from

Thermal4-12As an indication of the importance of keeping the thermal grease layer thin, ifthe thermal grease layer increases to 0.002 inch thick, the

5-1Measured Results Measured ResultsThis chapter shows the performance of the APA100 reference design. AnAudio Precision analyzer was used to produce

Total Harmonic Distortion + Noise5-25.1 Total Harmonic Distortion + NoiseThe APA100 has excellent total harmonic distortion + noise (THD+N).Figure 5−1

Total Harmonic Distortion + Noise5-3Measured ResultsFigure 5−3. APA100 THD+N vs Output Power With 4-W Load20510.50.10.050.0110 m 1 2 10 20 100 200THD

Output Power5-45.2 Output PowerThe APA100 can output over 100 W into 4 Ω. The curves in Figure 5−5 andFigure 5−6 show the output power versus supply v

Efficiency5-5Measured Results5.3 EfficiencyThe APA100 is a highly efficient class-D audio power amplifier. The efficiencyis greater than 85% efficient

Related Documentation From Texas InstrumentsivThis is an example of a warning statement.A warning statement describes a situation that could potential

Gain and Phase Response5-65.4 Gain and Phase ResponseThe APA100 is a closed−loop, class-D audio power amplifier with an LC outputfilter. The output fi

Supply Ripple Rejection5-7Measured Results5.6 Supply Ripple RejectionThe APA100 uses a closed loop which keeps the gain from changing withsupply volta

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Contentsv Contents1 EVM Overview 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ContentsviFigures1−1 THD+N vs Output Power (a), THD+N vs Frequency (b) 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1−2 APA100 EVM Block

1-1EVM Overview EVM OverviewThis reference design demonstrates how to make the TPA2001D1 and theTAS5111 into a 100-W class-D amplifier. The user’s gui

Features1-21.1 FeaturesThis reference design or evaluation module (EVM) features the TPA2001D1,TAS5111, and TLV2464A. For simplicity, this EVM is refe

EVM Basic Function/Block Diagram1-3EVM Overviewand NPN transistor circuit is used to create the 3-V supply for the TPA2001D1and TLV2464A; therefore, t