background image

User's Guide

SLOU215 – January 2008

DRV601EVM

This user’s guide describes the operation of the DRV601EVM stereo line driver evaluation module and
provides measurement data and design information such as the schematic, bill of materials, and
printed-circuit board layout.

Contents

1

Overview

......................................................................................................................

2

2

Quick Setup Guide

...........................................................................................................

3

3

Shutdown

.....................................................................................................................

5

4

Component Selection

.......................................................................................................

5

5

Layout Recommendations

..................................................................................................

7

6

DRV601EVM Performance

.................................................................................................

8

7

Related Documentation from Texas Instruments

......................................................................

19

8

Design Documentation

....................................................................................................

19

List of Figures

1

DRV601EVM

.................................................................................................................

2

2

DRV601 Functional Block Diagram

.......................................................................................

3

3

DRV601EVM Physical Structure

...........................................................................................

3

4

Power-Up/Down Sequence

.................................................................................................

5

5

Second-Order, Active Low-Pass Filter

....................................................................................

6

6

THD+N vs Voltage (600

)

.................................................................................................

9

7

THD+N vs Voltage (600

Ω

)

.................................................................................................

9

8

THD+N vs Voltage (100-k

load)

........................................................................................

10

9

THD+N vs Voltage (100-

load) Linear Scale

.........................................................................

10

10

THD+N vs Voltage (600-

Ω

Load)

........................................................................................

11

11

THD+N vs Voltage (100-k

Load)

.......................................................................................

11

12

THD+N vs Frequency (600-

Load)

.....................................................................................

12

13

THD+N vs Frequency (600-

Load) Using X7R Input Capacitors

..................................................

12

14

FFT Spectrum With –60-dBFS Tone

....................................................................................

13

15

Idle Noise FFT Spectrum (BTL)

..........................................................................................

13

16

Channel Separation

........................................................................................................

14

17

Channel Separation, 10x Lower Feedback Impedance

...............................................................

15

18

Frequency Response

......................................................................................................

15

19

Phase Response

...........................................................................................................

16

20

Pop/Click (Enable)

.........................................................................................................

17

21

Pop/Click (Disable)

.........................................................................................................

18

22

DRV601EVM PCB Component Placement Top

........................................................................

21

23

PCB Top Layer

.............................................................................................................

21

24

PCB Bottom Layer

.........................................................................................................

22

List of Tables

1

DRV601 Features

............................................................................................................

2

2

Recommended Supply Voltage

............................................................................................

5

3

DRV601EVM Specification

.................................................................................................

6

4

General Test Specifications

................................................................................................

8

PurePath Digital, DirectPath, FilterPro are trademarks of Texas Instruments.

SLOU215 – January 2008

DRV601EVM

1

Submit Documentation Feedback

Summary of Contents for DRV601EVM

Page 1: ...9 7 THD N vs Voltage 600 Ω 9 8 THD N vs Voltage 100 kΩ load 10 9 THD N vs Voltage 100 Ω load Linear Scale 10 10 THD N vs Voltage 600 Ω Load 11 11 THD N vs Voltage 100 kΩ Load 11 12 THD N vs Frequency 600 Ω Load 12 13 THD N vs Frequency 600 Ω Load Using X7R Input Capacitors 12 14 FFT Spectrum With 60 dBFS Tone 13 15 Idle Noise FFT Spectrum BTL 13 16 Channel Separation 14 17 Channel Separation 10x L...

Page 2: ...as independent shutdown control for the left and right audio channels This EVM is configured with two RCA phone input connectors and two RCA phone output connectors Power supply is connected via a two pin 2 54 mm pin header The EVM is configured with a gain of 2 V V Table 1 DRV601 Features KEY PARAMETERS Supply Voltage 1 8 V to 4 5 V Number of Channels 2 Load Impedance Minimum 600 Ω Output Voltage...

Page 3: ... Output capacitor less Shutdown button Figure 2 DRV601 Functional Block Diagram The physical structure of the DRV601EVM is shown in Figure 3 Figure 3 DRV601EVM Physical Structure This section describes the DRV601EVM board in regards to power supply and system interfaces It provides information regarding handling and unpacking absolute operating conditions and a description of the factory default s...

Page 4: ...the use of a grounded wrist strap at an approved ESD workstation CAUTION Failure to observe ESD handling procedures may result in damage to EVM components On opening the DRV601EVM package ensure that the following items are included 1 DRV601EVM board with one DRV601RTJ 1 pc PurePath Digital CD ROM If either of these items is missing contact the Texas Instruments Product Information Center nearest ...

Page 5: ... click and pop during power on and power off the shutdown pin should be kept low The preferred power up down sequence is shown in Figure 4 Figure 4 Power Up Down Sequence The charge pump flying capacitor C13 serves to transfer charge during the generation of the negative supply voltage The PVSS capacitor must be at least equal to the charge pump capacitor in order to allow maximum charge transfer ...

Page 6: ... above 4 5 V the DRV601 can shut down in an overvoltage protection mode to prevent damage to the device Many of the audio DACs used today require an external low pass filter to remove band noise This is possible with the DRV601 and the EVM is configured as a 40 kHz second order active Butterworth filter The topology chosen is the MFB Single Ended Further the DRV601 needs a ac coupling capacitor to...

Page 7: ... connected to ground or power Connecting this pad to power or ground prevents the device from working properly because it is connected internally to PVSS The SGND and PGND pins of the DRV601 must be routed separately back to the decoupling capacitor in order to provide proper device operation If the SGND pins are connected directly to each other the part functions without risk of failure but the n...

Page 8: ... 600 Ω 1 All electrical and audio specifications are typical values Table 6 Audio Performance AUDIO PERFORMANCE NOTES CONDITIONS THD N 600 Ω 0 02 Vrms 0 099 1 kHz Noise limited THD N 600 Ω 0 2 Vrms 0 009 1 kHz Noise limited THD N 600 Ω 2 Vrms 0 006 1 kHz THD N 100 kΩ 0 02 Vrms 0 099 1 kHz Noise limited THD N 100 kΩ 0 2 Vrms 0 009 1 kHz Noise limited THD N 100 kΩ 2 Vrms 0 005 1 kHz Dynamic Range 10...

Page 9: ...1 25 1 5 1 75 2 2 25 2 5 2 75 3 3 25 3 5 3 75 1 V Output Voltage Vrms O 1 8 V DVDD 3 3 V DVDD 4 5 V DVDD DRV601EVM Performance Figure 6 THD N vs Voltage 600 Ω The THD N from 10m Vrms to approximately 0 5 Vrms is dominated by noise Figure 7 THD N vs Voltage 600 Ω Here the THD N versus output voltage is shown with linear scale this makes it easier to see where clipping occurs Clipping is often defin...

Page 10: ... 25 2 5 2 75 3 3 25 3 5 3 75 1 V Output Voltage Vrms O 1 8 V DVDD 3 3 V DVDD 4 5 V DVDD DRV601EVM Performance Figure 8 THD N vs Voltage 100 kΩ load The THD N in the range from 10mVrms to 1Vrms is completely dominated by noise Figure 9 THD N vs Voltage 100 Ω load Linear Scale Here the THD N versus output voltage is shown with linear scale this makes it easier to see where clipping occurs Clipping i...

Page 11: ...Voltage Vrms O THD N Total Harmonic Distortion Plus Noise dB 3 3 V DVDD DRV601EVM Performance Figure 10 THD N vs Voltage 600 Ω Load Here the clipping is shown with a 3 3 V supply and 10 tolerance It shows that even with a low DVDD 3 3 V 10 the DRV601 can achieve the 2 Vrms with a THD N less than 1 2 Vrms is equal to 2 848 Vpeak that is only 142 mV drop from the 2 97 V supply Figure 11 THD N vs Vol...

Page 12: ... a 1 µF film capacitor for ac coupling of the input signal If a lower cost ceramic capacitor like a X7R is used higher THD at low frequencies should be expected Y5V capacitors show even higher THD and cannot be recommended at all Figure 13 THD N vs Frequency 600 Ω Load Using X7R Input Capacitors The X7R capacitors raise the 20 Hz THD from 0 003 to 0 04 or 0 07 20 times higher If the cost requireme...

Page 13: ...ce Reference voltage is 2 Vrms FFT size 16k Figure 14 FFT Spectrum With 60 dBFS Tone This spectrum corresponds to a dynamic range of 104 dB A weighted SNR measures to 104 dB A weighted 12 µVrms This noise floor is dominated by the feedback resistor network impedance level This can be improved by lowering the impedance level a 10x lower impedance level lowers the noise floor to 110 dB 6 µVrms Refer...

Page 14: ...eparation Left to right cross coupling and right to left cross coupling are not exactly the same a difference of 15 dB is seen at 1 kHz The channel separation is more than 80 dB in both cases The cause for the cross coupling is the high impedance of the feedback network If a lower cross coupling is wanted the feedback impedance can be lowered this has an influence on the input coupling capacitor t...

Page 15: ...kHz Figure 17 Channel Separation 10x Lower Feedback Impedance With a 10x lower impedance in the feedback network the channel separation improved significantly and is now 100 dB at 1 kHz The lower impedance network also improved the noise floor and now the dynamic range is 110 dB equal to 6 µVrms noise The parts used are R11 R12 1k5 R16 R17 3k0 R14 R15 4k7 C17 C18 3n3 C19 C20 330 pF C15 C16 10 µF a...

Page 16: ...of 15kR The low pass second order filter implemented gives a 3 dB approximately at 35 kHz and the response is 13 dB down at 80 kHz No input signal is applied The measurement results are presented both in a time domain and in a frequency domain The resistor load is 600 Ω The power supply is applied and then the shutdown signal is released The shutdown signal is used to trigger the measuring system ...

Page 17: ... Performance Figure 20 Pop Click Enable The DRV601 shows very low pop during enable only two small high frequency spikes can be seen The measurements are made with reference to 2 Vrms 0 dB 2 mV 60 dBr No input signal is applied The measurement results are presented both in a time domain and in a frequency domain No input signal applied Load 600 Ω SLOU215 January 2008 DRV601EVM 17 Submit Documentat...

Page 18: ...90 80 70 60 50 40 30 20 10 300 30k 500 1k 2k 5k 10k 20k f Frequency Hz Amplitude dBr DRV601EVM Performance Figure 21 Pop Click Disable During power down the click is even lower than during power on enable A very small click is seen DRV601EVM 18 SLOU215 January 2008 Submit Documentation Feedback ...

Page 19: ... pin 13 Gain R16 R11 R17 R12 2 0 Low Pass filter 40kHz 2nd Order Butterworth High Pass filter R11 C15 R12 C16 aprox 10Hz Line Driver Input Output C19 33 pF 2 1 R13 1 2 C20 33 pF 2 1 3 3 V 3 3 V 1 8V to 4 5V Power supply C11 2 1 GND SW1 Switch 1 4 2 3 R14 1 2 J21 Phono socket 2 3 4 1 R15 47 kW 1 2 J22 Phono socket 2 3 4 1 GND GND R16 30 kW 1 2 R11 15 kW 1 2 R17 30 kW 1 2 J10 Header 1 2 GND 1 F m 1 ...

Page 20: ... R16 R17 30k 100 mW 5 0603 Thick Film Resistor Yageo RC0603JR 0730KL 2 R18 R19 10R 100 mW 5 0603 Thick Film Resistor Yageo RC0603JR 0710RL 1 SW1 Switch 6 mm SMD Tactile Switch Omron B3S 1000 1 U1 DRV601 DirectPath Audio Line Driver with external Texas Instruments DRV601RTJT gain setting QFN 20 Table 9 PCB Specifications BOARD IDENTIFICATION A834 PCB 001 2 00 BOARD TYPE Double sided plated through ...

Page 21: ... Layout Design Documentation Gerber files are available on the EVM page for download Figure 22 DRV601EVM PCB Component Placement Top Figure 23 PCB Top Layer SLOU215 January 2008 DRV601EVM 21 Submit Documentation Feedback ...

Page 22: ...www ti com Design Documentation Figure 24 PCB Bottom Layer 22 DRV601EVM SLOU215 January 2008 Submit Documentation Feedback ...

Page 23: ...product This notice contains important safety information about temperatures and voltages For additional information on TI s environmental and or safety programs please contact the TI application engineer or visit www ti com esh No license is granted under any patent right or other intellectual property right of TI covering or relating to any machine process or combination in which such TI product...

Page 24: ...ice and is an unfair and deceptive business practice TI is not responsible or liable for any such statements TI products are not authorized for use in safety critical applications such as life support where a failure of the TI product would reasonably be expected to cause severe personal injury or death unless officers of the parties have executed an agreement specifically governing such use Buyer...

Page 25: ...мые продукты мы предоставляем гарантию Осуществляем поставки продукции под контролем ВП МО РФ на предприятия военно промышленного комплекса России а также работаем в рамках 275 ФЗ с открытием отдельных счетов в уполномоченном банке Система менеджмента качества компании соответствует требованиям ГОСТ ISO 9001 Минимальные сроки поставки гибкие цены неограниченный ассортимент и индивидуальный подход ...

Reviews: