Page 3 - Preface; Read This First; About This Manual; This is an example of a caution statement.
Information About Cautions and Warnings iii Preface Read This First About This Manual This user’s guide describes the characteristics, operation, and the use of theAPA100 reference design board. It covers all pertinent areas involved toproperly use this reference design board along with the devices ...
Page 4 - This is an example of a warning statement.; Related Documentation From Texas Instruments
Related Documentation From Texas Instruments iv This is an example of a warning statement. A warning statement describes a situation that could potentiallycause harm to you. The information in a caution or a warning is provided for your protection. Readeach caution and warning carefully. Related Doc...
Page 5 - Contents; EVM Overview
Contents v Contents 1 EVM Overview 1-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Features 1-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 6 - Figures
Contents vi Figures 1−1 THD+N vs Output Power (a), THD+N vs Frequency (b) 1-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1−2 APA100 EVM Block Diagram 1-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2−1 APA100 Split Plane Top Layo...
Page 7 - Topic; Chapter 1
1-1 EVM Overview EVM Overview This reference design demonstrates how to make the TPA2001D1 and theTAS5111 into a 100-W class-D amplifier. The user’s guide discusses how theTPA2001D1 is used as an analog input class-D modulator. The analogmodulator is input to the TAS5111, which is an H-bridge that e...
Page 8 - Power Requirements; Supply Voltage
Features 1-2 1.1 Features This reference design or evaluation module (EVM) features the TPA2001D1,TAS5111, and TLV2464A. For simplicity, this EVM is referred to as the APA100EVM to cover all parts that are supported in this user’s guide. The APA100EVM is an evaluation module designed for a quick and...
Page 9 - resistor to filter any noise. Test point 3V; EVM Basic Function/Block Diagram
EVM Basic Function/Block Diagram 1-3 EVM Overview and NPN transistor circuit is used to create the 3-V supply for the TPA2001D1and TLV2464A; therefore, the user only needs to apply the single-supplyvoltage. A+ supply is used for powering the TAS5111 and is input for the zenerdiode/NPN transistor cir...
Page 10 - Figure 1−2. APA100 EVM Block Diagram
EVM Basic Function/Block Diagram 1-4 Figure 1−2. APA100 EVM Block Diagram Audio Input Gain (TLV2464) Feedback and Integrator(TLV2464) AudioOutput Analog Input Class-D Modulator TPA2001D1 H-Bridge (TAS5111)
Page 11 - PCB Design; Chapter 2
2-1 PCB Design PCB Design This chapter gives layout guidelines for the APA100 reference design. Topic Page 2.1 PCB Layout 2-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Bill of Materials 2-6 . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 12 - Split Ground Plane; Figure 2−1. APA100 Split Plane Top Layout
PCB Layout 2-2 2.1 PCB Layout The critical part of the design lies particularly in the layout process. The EVMlayout should be followed exactly for optimal performance. The main concernis the placement of components and the proper routing of signals. Place thebypass/decoupling capacitors as close as...
Page 13 - Figure 2−2. APA100 Split Plane Bottom Layout; Minimize trace length to C29, and use wide traces.; Analog Section Layout; sensitive node of the reference design.
PCB Layout 2-3 PCB Design Figure 2−2. APA100 Split Plane Bottom Layout 2.1.2 H-Bridge Layout The H-bridge is laid out based on recommendations from the TAS5111 datasheet and follows the same pattern as the DAVREF100 EVM board. 1) Keep local decoupling and bootstrap capacitors and resistors close to ...
Page 14 - operational amplifier circuitry.; PCB Layers; Figure 2−3. Top Copper and Silkscreen
PCB Layout 2-4 3) Use a split ground plane to keep high switching ground currents from the operational amplifier circuitry. 4) Place decoupling capacitors close to the TLV2464A and TPA2001D1 5) Place RC filter capacitors (C20, C23, and C24) close to the operational amplifier, with capacitor grounds ...
Page 15 - Figure 2−4. Bottom Copper and Silkscreen
PCB Layout 2-5 PCB Design Figure 2−4. Bottom Copper and Silkscreen Figure 2−5. Drill Drawing SIZE QTY STM PLTD 18 4 PLTD 28 40 PLTD 42 21 PLTD 89 3 PLTD 116 6 PLTD 140 4 PLTD 3.4 INCH 2.5 INCH
Page 16 - Bill of Materials; Table 2−1. Parts List
Bill of Materials 2-6 2.2 Bill of Materials Table 2−1. Parts List Reference Qty Value Manufacturer Part Number Description C23,24 2 22 pF TDK C1608C0G1H220J 50 V, size 603, COG, 5% C13,19,20,R25 4 56 pF TDK C1608C0G1H560J 50 V, size 603, COG, 5% C6,9,11,12,14,17,18,21,49,50 10 220 pF TDK C1608X7R1H2...
Page 17 - Schematic
Page 19 - EVM Operation; Chapter 3
3-1 EVM Operation EVM Operation This chapter covers in detail the operation of the APA100 EVM to guide theuser in evaluating the audio power amplifier and in interfacing the APA100EVM to an audio input and power supply. Topic Page 3.1 Quick Start 3-2 . . . . . . . . . . . . . . . . . . . . . . . . ....
Page 20 - Follow these steps to use the APA100 EVM.; Figure 3−1. Quick Start Module Map; Power Supply; ) Ensure that all external power sources are set to off.; Inputs and Outputs; ) Ensure that the signal source level is set to minimum.
Quick Start 3-2 3.1 Quick Start Follow these steps to use the APA100 EVM. APA100 audio input connection can be made via a phono jack (J1), or by sol-dering to its pins. The power supply and outputs can be connected with bananaconnectors or wires via screw terminals. Figure 3−1 shows numbered callout...
Page 21 - Power Up; The EVM begins operation.; Power−Up/Down Sequence
Power−Up/Down Sequence 3-3 EVM Operation Power Up 6) Press and hold the RESET button (S1) 7) Verify correct voltage and input polarity, and set the external power supply to on. 8) Depress the RESET button (S1). The EVM begins operation. 9) Adjust the signal source level as needed. 10) Hold RESET but...
Page 22 - Changing the Gain; Front−end Gain
Changing the Gain 3-4 3.5 Changing the Gain The 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 V/V), and a back-end gain of 27 dB(−22.4 V/V), for a total of 31.4 dB (37.3 V/V). The back-end gain needs to bekept constant, because it is set by ...
Page 23 - Technical Information; Chapter 4
4-1 Technical Information Technical Information This chapter goes into the details of the design of the 100-W amplifier. Thedesign comprises the modulator, H-bridge, operational amplifier, feedbackloop, LC filter, and thermal. Topic Page 4.1 Feedback System Design 4-2 . . . . . . . . . . . . . . . ....
Page 24 - cary to cancel two poles of the LC filter.
Feedback System Design 4-2 4.1 Feedback System Design The APA100 EVM uses feedback to lower distortion, increase supply ripplerejection, and make the gain not change with supply voltage. This section goesthrough the following steps to close the loop. 1) Take feedback at TAS5111 outputs before the LC...
Page 25 - Figure 4−2. Open− and Closed−Loop Frequency Response; Phase Margin
Feedback System Design 4-3 Technical Information operational amplifier (R22, R23, C20, C23, and C24) was eventually reducedfrom 400 kHz to 252 kHz to optimize performance; compensation for this isdiscussed later. Notice that in Figure 4−8, the switching frequency of eachoutput is 250 kHz, but the di...
Page 26 - Canceling Zero; Gain of integrator = Z; Figure 4−4. APA100 Integrator Design
Feedback System Design 4-4 Figure 4−3. Open− and Closed−Loop Frequency Response With TPA2001D1 Pole and Canceling Zero Open Loop Gain Closed Loop Gain Fc = 40 kHz 0 Degrees −90 Degrees Phase Gain − dB Frequency − Hz 20 dB / Decade X F P0 F P0* 10 F P0 10 X X X 80 kHz >400 kHz Now that the poles a...
Page 28 - Figure 4−5. PSPICE Circuit for Simulating the Feedback; The circuit was simulated to show 40-kHz bandwidth with 49
Feedback System Design 4-6 Instead of calculating the bandwidth, PSPICE was used with a linearizedcircuit (see Figure 4−5) to simulate and adjust the component values toapproximately 40-kHz bandwidth. Then, Equations 7 and 8 were used to setthe poles and zeros. The first op amp (U1) in the simulatio...
Page 29 - Figure 4−6. PSPICE Simulation of Open−Loop Response
TPA2001D1 (Class-D Modulator) 4-7 Technical Information Figure 4−6. PSPICE Simulation of Open−Loop Response f − Frequency − Hz TAS5111Output (dB) IntegratorOutput (dB) 200 100 −0 −100 −200 −300 100 1 k 10 k 100 k 1 M Phase ( 5 ) 4.2 TPA2001D1 (Class-D Modulator) The TPA2001D1 was chosen as an excell...
Page 30 - Figure 4−8. TPA2001D1 Inputs and Outputs With 20−kHz Sine Wave
TPA2001D1 (Class-D Modulator) 4-8 Figure 4−7. TPA2001D1 Block Diagram _ + Gain Adj. _ + + _ cmv Gain Adj. Rs2 Rs1 _ + _ + Cint2 Cint1 _ + Deglitch Logic Deglitch Logic Comparator Integrator Pre-Amp Gate Drive Gate Drive TTLInputBuffers 2 SDZ Gain Biases and References RampGenerators Startup Protecti...
Page 31 - ) High output current
TAS5111 (H-Bridge) 4-9 Technical Information For more information concerning the TPA2001D1 operation and modulationscheme, see the TPA2001D1 data sheet http://focus.ti.com/docs/prod/folders/print/tpa2001d1.html 4.3 TAS5111 (H-Bridge) The TAS5111 converts the PWM signal from the 3-V peak-to-peak outp...
Page 32 - LC Filter; The LC filter serves two purposes in this design.; The inductor must have 8
LC Filter 4-10 4.5 LC Filter The LC filter serves two purposes in this design. 1) Reduces EMI 2) Enables overcurrent (OC) protection. The outputs of the TAS5111 are square waves with fast rise and fall times. Thesquare waves produce harmonics up to 500 MHz. The speaker wire makestransmission lines f...
Page 33 - Thermal
Thermal 4-11 Technical Information 4.6 Thermal The APA100 thermal issues lie with the TAS5111. The following thermalcalculations and tables are taken from the TAS5111 data sheet. The TAS5111is designed to be interfaced directly to a heatsink using a thermal interfacecompound (for example, Wakefield ...
Page 35 - Measured Results; Chapter 5
5-1 Measured Results Measured Results This chapter shows the performance of the APA100 reference design. AnAudio Precision analyzer was used to produce the graphs in this chapter. Topic Page 5.1 Total Harmonic Distortion + Noise 5-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 Out...
Page 36 - Total Harmonic Distortion + Noise; −1 and Figure; Load; Load
Total Harmonic Distortion + Noise 5-2 5.1 Total Harmonic Distortion + Noise The APA100 has excellent total harmonic distortion + noise (THD+N).Figure 5−1 and Figure 5−2 show the THD+N versus frequency, and Figure 5−3 and Figure 5−4 show THD+N vs output power. A 30-kHzbandwidth limit was used on the ...
Page 38 - Output Power; . The curves in Figure 5−5 and; Figure 5−5. APA100 Output Power vs Supply Voltage With 4-; Figure 5−6. APA100 Output Power vs Supply Voltage With 8-
Output Power 5-4 5.2 Output Power The APA100 can output over 100 W into 4 Ω . The curves in Figure 5−5 and Figure 5−6 show the output power versus supply voltage. Figure 5−5. APA100 Output Power vs Supply Voltage With 4- W Load 0 20 40 60 80 100 120 18 20 22 24 26 28 P O @ 10% THD P O @ 1% THD P O −...
Page 39 - Efficiency; load. The efficiency plot is shown; Figure 5−7. APA100 Efficiency vs Output Power With 4-
Efficiency 5-5 Measured Results 5.3 Efficiency The APA100 is a highly efficient class-D audio power amplifier. The efficiencyis greater than 85% efficient with 4- or 8- Ω load. The efficiency plot is shown in Figure 5−7. Figure 5−7. APA100 Efficiency vs Output Power With 4- W Load 100 90 80 70 60 50...
Page 40 - Gain and Phase Response; curve rolls off sooner than the 8-; Figure 5−8. APA100 Gain vs Frequency With 4-; V rms. The amplifier can output 19 Vrms. This
Gain and Phase Response 5-6 5.4 Gain and Phase Response The APA100 is a closed−loop, class-D audio power amplifier with an LC outputfilter. The output filter and the 39-kHz loop bandwidth limit the bandwidth of theAPA100 reference design. The gain versus frequency curve is shown inFigure 5−8. The 4-...
Page 41 - Supply Ripple Rejection
Supply Ripple Rejection 5-7 Measured Results 5.6 Supply Ripple Rejection The APA100 uses a closed loop which keeps the gain from changing withsupply voltage and improves the supply ripple rejection ratio (k SRR ) over an open−loop class-D amplifier. The supply ripple rejection ratio versusfrequency ...
