Manuals / Texas Instruments / Home Audio / Stereo Amplifier

Texas Instruments APA100 manual Power−Up/Down Sequence, Reset Button/Mute, Error Signals

Models: APA100

1 42

Download 42 pages 18.78 Kb

Page 21

3.2 Power−Up/Down Sequence

Power−Up/Down Sequence

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 button (S1) while powering down

3.2 Power−Up/Down Sequence

The RESET pin of the TAS5111 needs to be held low while turning on power. This enables the feedback loop to get settled and avoids a loud pop. An RC filter was placed on the board to help with this, but for optimal pop perfor- mance, hold the RESET button (S1) during start-up. The RESET button should also be held during power-off to reduce power-off pop.

3.3 Reset Button/Mute

The reset button (S1) controls the RESET pin of the TAS5111. This pin keeps the outputs of the TAS5111 from switching and can also be used as a mute button. This is valuable because it allows the feedback loop to stay active and minimizes the pop going into and coming out of mute.

3.4 Error Signals

The APA100 board has test points to monitor the error signals from the TAS5111. Test points SD and OTW gives TAS5111 state information as described in Table 3−1.

Table 3−1. TAS5111 Error Decoding

OTW SD		DESCRIPTION
0	0	Overtemperature error ( Tj>150_C )

0	1	Overtemperature warning ( Tj >125_C )

1	0	Overcurrent (>8 A) or undervoltage (GVDD < 7 V) error

1	1	Normal operation, no errors/warnings

EVM Operation

3-3

Image 21

Texas Instruments APA100 manual Power−Up/Down Sequence, Reset Button/Mute, Error Signals, 1. TAS5111 Error Decoding

Contents

User’s Guide Audio Power AmplifiersAPA100 AugustIMPORTANT NOTICE ProductsApplications Read This First How to Use This ManualAbout This Manual Information About Cautions and WarningsFCC Warning Related Documentation From Texas InstrumentsData Sheets This is an example of a warning statementContents Tables FiguresChapter EVM OverviewPage Topic1.1 Features 1.2 Power Requirements1.2.1Supply Voltage 1.3 EVM Basic Function/Block Diagram EVM Basic Function/Block DiagramEVM Overview Feedback EVM Basic Function/Block DiagramIntegrator TLV2464Schematic PCB DesignChapter Page2.1.1Split Ground Plane 2.1 PCB Layout2.1.2H-BridgeLayout 2.1.3Analog Section LayoutFigure 2−2. APA100 Split Plane Bottom Layout Figure 2−3. Top Copper and Silkscreen 2.1.4PCB LayersFigure 2−5. Drill Drawing Figure 2−4. Bottom Copper and SilkscreenPCB Layout PCB Design2.2 Bill of Materials Table 2−1. Parts ListBill of Materials 2.3 Schematic SchematicPCB Design Page Chapter EVM OperationPage TopicFigure 3−1. Quick Start Module Map 3.1 Quick Start3.3 Reset Button/Mute 3.2 Power−Up/Down Sequence3.4 Error Signals Table 3−1. TAS5111 Error Decoding3.5 Changing the Gain Chapter Technical InformationPage TopicFigure 4−1. APA100 Block Diagram 4.1 Feedback System DesignPhase Margin + 180 Phase at Fc Figure 4−4. APA100 Integrator Design Closed−loop gain + 1.5 0 C10 V1 1 0 4.2 TPA2001D1 Class-DModulator TPA2001D1 Class-DModulator Figure 4−7. TPA2001D1 Block DiagramCh1: 3V/Div Ch2: 3V/Div Ch3: 3V/Div Ch4: 1V/Div t − Time −4.3 TAS5111 H-Bridge 4.4 TLV2464A Gain Setting and FeedbackFigure 4−9. APA100 Output Filter 4.5 LC FilterTable 4−1. TAS5111 Thermal Table 4.6 ThermalAs an indication of the importance of keeping the thermal grease layer thin, if the thermal grease layer increases to 0.002 inch thick, the required heatsink thermal resistance changes to 2.4C/W Chapter Measured ResultsPage TopicTotal Harmonic Distortion + Noise 5.1 Total Harmonic Distortion + NoiseMeasured Results Total Harmonic Distortion + NoiseOutput Power 5.2 Output Power5.3 Efficiency EfficiencyMeasured Results 5.4 Gain and Phase Response 5.5 Signal-to-NoiseRatio SNRGain and Phase Response 5.6 Supply Ripple Rejection Supply Ripple RejectionMeasured Results