Texas Instruments DEM-PCM1717 User Manual

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DEM-PCM1717

®

DEM-PCM1717-1DEM-DAI1717

EVALUATION FIXTURE

DEM-DAI1717

FEATURES

DEM-PCM1717

Basic evaluation board for the PCM1717 requires an external audio processor for connection to digital audio source.

DEM-PCM1717-1

DEM-PCM1717plus Windows evaluation software and connector.

DEM-DAI1717

Evaluation board for the PCM1717 including evaluation software and Digital Audio Interface.

BLOCK DIAGRAMS

EVALUATION SOFTWARE AND CONNECTOR

Centronics Connector

6 Pin Connector

+VCC

 

GND

Evaluation Software

 

 

International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111• Twx:910-952-1111Internet:http://www.burr-brown.com/• FAXLine: (800)548-6133(US/Canada Only) • Cable: BBRCORP • Telex:066-6491• FAX: (520)889-1510• Immediate Product Info: (800)548-6132

®

© 1996 Burr-BrownCorporation

1

DEM-PCM1717

1996

LI-475

Printed in U.S.A. July,

SBAU019

BLOCK DIAGRAMS (CONT)

DEM-PCM1717

Audio Data

LRCK/BCK/DATA Lch Direct Out

256/384fs

PCM1717

Lch Capacitive Out

Control Data

Rch Direct Out

ML/MC/MD

 

 

Rch Capacitive Out

GND

+VCC

DEM-DAI1717

DAI

DAC

LPF

 

 

Lch Direct Out

COAX

 

 

 

 

Lch Low Pass Out

SPDIF

PCM1717

OPA2604

CS8412

OPT

 

 

 

 

Rch Low Pass Out

 

 

Rch Direct Out

GND

+VCC

–VS GND +VS

The information provided herein is believed to be reliable; however, BURR-BROWNassumes no responsibility for inaccuracies or omissions.BURR-BROWNassumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party.BURR-BROWNdoes not authorize or warrant anyBURR-BROWNproduct for use in life support devices and/or systems.

®

 

DEM-PCM1717

2

 

DEM-PCM1717

The DEM-PCM1717is the basic evaluation fixture for the PCM1717 ΔΣ audio DAC. This fixture provides an easy way to connect power, data, and interface signals to the DAC.

Figure 1 shows the block diagram of the DEM-PCM1717.The user must supply 4 digital audio signals, power, and mode control signals. The DAC will then provide two channels of either directly or capacitively coupled analog outputs.

The PCM1717 can be operated either in a hardware or software mode. In the software mode either external logic or a processor is used to program four registers internal to the PCM1717. (Consult the data sheet for additional information).

The hardware mode can be evaluated using this fixture by use of the on board DIP switches. These switches are connected to pins on the PCM1717 which force either power or ground to the pin. In the hardware mode some of the features of the PCM1717 can be exercised. The selection between the hardware and software mode is done using the mode switch on the DEM-1717.Figure 2 shows the switch settings and the resulting functions attained for the PCM1717. The switches operate in an active low condition.

ML MC MD RSTB GND +VCC

CN2

S1

4

 

CN1

5

 

 

CLKO

 

 

XTI

 

 

BCK

 

 

LRCK

 

PCM1717E

DIN

 

 

GND

 

 

CN3

VOL • C

VOL • D

VOR • D

VOR • C

ZO

GND

R1

+VCC

FIGURE 1. DEM-PCM1717Block Diagram.

 

 

 

 

DEM-PCM1717

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Low

 

Mute

 

Off

 

Off

 

 

Reset

 

Hardware

 

On

 

On

 

48kHz

 

44.1kHz

 

 

Off

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

De-Emphasis

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

High

 

Mute

 

44.1kHz

 

48kHz

 

 

Reset

 

Software

 

Off

 

Off

 

32kHz

 

32kHz

 

 

On

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ML

 

MC

 

MD

RSTB

 

Mode

 

 

FIGURE 2. DEM-PCM1717Switch Settings.

HARDWARE DESCRIPTION

Figure 3 shows the schematic diagram of the DEM-PCM1717evaluation board.

Figure 4 illustrates the PC board design and component placement for the DEM-PCM1717evaluation board. Note on the parts layout that there are 3 connectors CN1, CN2, and CN3. CN1 is used to connect the digital audio signals to the PCM1717. CN2 is used connect the control lines for the PCM1717 as well as power and ground. CN3 is used to access the audio output from the PCM1717. The analog outputs are available asDC-coupled(VOR-D,VOL-D)orac-coupled(VOR-C,VOL-C).The DC coupled output is referred to ground, and the ACcoupled output is referred to VCC/2, typically 2.5V. There is also a connection for the output of the zero detect flag. Use of this pin requires a pull-

up resistor, R1. This resistor is labeled R1 on the schematic and the board and a typical value is 4.7kΩ.

The crystal (U1) is not included.

®

3

DEM-PCM1717

 

 

 

GND

DIN

LRCK

 

BCK

XTI

CLKO

 

 

 

 

 

 

CN1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CS1

 

 

CS2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

S1

 

 

 

 

 

 

 

 

 

 

 

 

 

ML/MUTE

 

 

 

 

 

 

 

 

 

XTAL

 

 

MC/DM1

 

 

 

 

 

 

 

 

 

U1

 

 

 

 

 

 

 

 

 

 

 

 

 

MD/DM0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PCM1717E

 

RSTB

 

 

 

 

 

 

 

 

1

XTI

 

20

 

MODE

 

 

 

 

 

 

 

 

2

 

XTO

 

 

 

 

 

+

C4

 

 

 

DGND

 

19

 

 

 

 

 

 

 

 

3

 

CLKO

 

 

 

 

 

 

2.2µF

 

 

 

VDD

 

18

 

 

 

 

ML

 

 

 

 

 

4

 

ML/MUTE

 

 

 

 

 

 

 

 

 

LRCIN

 

17

 

 

 

 

 

 

 

 

 

 

5

 

MC/DM1

 

 

 

 

 

 

 

 

 

 

 

 

16

 

 

 

 

MD

 

 

 

 

 

 

DIN

 

MC/DM0

 

 

 

 

 

 

 

 

 

6

BACKIN

15

 

 

 

 

 

 

 

 

 

 

7

RSTB

 

C5

 

 

MC

 

 

 

 

 

 

 

14

 

 

 

 

 

 

 

 

8

ZERO

 

MODE

 

10µF

 

 

 

 

 

 

C6

+

D/C_R

 

13

 

+

 

 

RSTB

 

 

 

 

 

9

 

D/C_L

 

 

 

 

 

 

 

 

10µF

 

 

12

 

 

 

 

 

 

 

 

10

VOUTR

 

VOUTL

 

 

 

 

GND

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

11

 

 

 

 

 

 

 

 

 

 

 

AGND

 

VCC

+ C3

 

 

 

+VCC

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2.2µF

 

+

 

 

 

 

 

 

 

 

 

 

C2

C1

 

 

 

 

 

 

 

 

 

 

 

 

CN2

 

 

 

 

 

 

 

 

 

 

0.1µF

 

100µF

 

R1

 

 

 

C8+

 

+

C7

 

 

 

 

 

 

 

 

 

10µF

 

 

10µF

 

 

 

 

 

 

CN3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

GND

ZO

VOR-CVOR-DVOL-DVOL-C

XTAL, CS1, CS2, R1: Not Installed.

FIGURE 3. DEM-PCM1717Schematic.

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DEM-PCM1717

4

 

FIGURE 4. DEM-PCM1717Parts Layout and Trace Design.

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5

DEM-PCM1717

 

 

DEM-PCM1717-1

This demo board kit consist of a DEM-PCM1717hardware board, together with an interface cable, for connecting theDEM-PCM1717to power and connecting the software control lines to anIBM-PCparallel port.DEM-PCM1717also includes evaluation software, described later under Software Description. The interface cable connects to the connector CN2, a source of +5V and ground, and the parallel port of an IBM compatible PC. Figure 5 shows the block diagram and connection for theDEM-PCM1717-1.

DEM-DAI1717

DEM-DAI1717is a complete evaluation fixture, including an SPDIF receiver, PCM1717 and an analog postlow-passfilterDEM-DAI1717also includes evaluation software.

PCM1717 contains features which can be programmed externally. These features include a 256-stepdigital attenuator, data interface format, word length, output format, etc. Refer to the PCM1717 data sheet for a complete description of these special functions.

PCM1717’s special functions are programmed via a 3-wireserial interface. This type of control is commonly referred to as serial or software control. The penalty for using this mode is that the DAC must be controlled via external microprocessor or logic. But since most digital audio systems usually contain a microprocessor or micro controller, component count is not always increased.

DEM-DAI1717utilizes the parallel port of anIBM-compat-ible PC to implement the3-wireserial programming interface. The evaluation software runs on Windows© Operating System.

The DEM-DAI1717evaluation board consists of three main sections or functions. The audio interface section consists of an electrical (RCA jack) or fiber optics connector to the SPDIF input. The input signal is processed into a standard 3- wire serial digital audio interface with the SPDIF receiver. The DAC section consists of the PCM1717E audio DAC and its associated circuitry. The active filter section uses an OPA2604 op amp to implement a2nd-orderfilter for reduction ofout-of-bandnoise. Figure 6 shows the block diagram of theDEM-DAI1717system board.

LRCK, BCK

MC, MD, ML

DIN, SYSCLK

DEM-PCM1717

 

Left/Right Audio

PC

 

 

Centronics

 

+5V, Ground

 

Software

FIGURE 5. DEM-PCM1717-1Interface Connection.

DAI-Settings

Mode Settings

Centronics

S0, S1, S2

 

S3

 

 

 

 

 

 

 

SPDIF Optical

 

 

 

Lch Direct Out

 

 

 

 

TORX

 

 

V out L

 

 

 

 

Lch Filtered Out

174

 

 

 

 

 

 

 

DAI-Receiver

JP

DAC

OPA2604

 

256fs

Low-Pass

RCA: Connector

CS8412

 

PCM1717

LRCK

FIlter

 

RCA - 75Ω

 

 

BCK

 

V out R

 

 

 

 

Rch Filtered Out

 

 

 

 

 

DATA

 

 

 

 

 

 

 

Rch Direct Out

GND +VCC –VS GND +VS

FIGURE 6. DEM-DAI1717Block Diagram.

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DEM-PCM1717

6

 

DEM-DAI1717also allows for operation in the hardware mode. In this mode, the special functions are limited to deemphasis frequency selection, soft mute and reset. These hardware features are controlled with DIP switches, and no PC connection is required.

DEM-DAI1717SYSTEM CONTENTS

DEM-DAI1717Evaluation Board

DEM-DAI1717Software on a 3.5" high density disc

DEM-DAI1717Evaluation Board contains a SPDIF interface, an interface for theIBM-PC,and an external low pass filter for the DAC itself.

DEM-DAI1717Software must be installed under the Windows version 3.1 or Windows 95.

DEM-DAI1717SYSTEM REQUIREMENTS

An IBM compatible PC with a 386/25MHz processor

Windows 3.1 or newer

A parallel port with Centronics cable interface.

A source of digital audio data in the SPDIF format

Installed and working DEM-PCM1717Software and System Board

INSTALLING THE DEM-PCM1717SOFTWARE

It is recommended to install the DEM-PCM1717software to the hard disk drive. It is possible to run the program from the floppy, but not recommended due to operating speed considerations. It is also recommended to use adesk-topcomputer. Certain laptop PCs havenon-standardparallel ports which may not be compatible withDEM-DAI1717.

From the “File Manager” select the “Create Directory” from the “File Menu” and create a directory called “pcm17dem” on the hard drive that the software is to be installed on. Copy all seven files from the floppy disk’s “pcm17dem” subdirectory.

CREATING AN ICON FOR THE

DEM-1717PROGRAM

The following procedure should be followed to create an Icon for starting the DEM-PCM1717software.

From the Windows Main Menu select Windows Setup.

From the Windows Setup select Set Up Applications selection. From this Menu select the Ask you to specify an application selection.

The next window will ask for the Application Path and Filename to be specified, assuming that drive C: was the drive the software was copied to then this path and filename should be typed in as C:/PCM17DEM/PCM17DEM.EXE.

• Also from the previous menu the Program Group that the icon should be added to can be selected. The default choice of Applications is a good choice for this selection.

For the rest of this manual it will be assumed that the software was installed from the A: drive to the C: hard drive and that an Icon was created for the software under the Applications program group.

CONFIGURING THE PCM17DEM.INI FILE

The DEM-PCM1717software controls the software mode of the PCM1717 by sending messages to the I/O address of the parallel port of an IBM compatible PC. In order for these control signals to reach theDEM-DAI1717evaluation board the software must be configured for the parallel port to be used. The contents of the default pcm17dem.ini file is as follows:

[PCM17DEM]

PCMIFADR = &H3BC

The last three characters of the second line of this program specify the I/O address will send instructions to the software. Typically the IBM-PChas three I/O addresses that are used for parallel or printer communications. The default address for theDEM-PCM1717software is 3BC. If the port that is being used to control theDEM-DAI1717system board is different from this default address then the 3BC address should be changed to that address.

Typical port assignments are as follows:

If the DEM-DAI1717system board is connected to LPT1 on anIBM-PCmade in the U.S. then the pcm17dem.ini should be modified to read

3BC

International Printer Port address

 

 

378

US LPT1 address

 

 

278

US LPT2 address

 

 

[PCM17DEM]

PCMIFADR = &H378

If the DEM-DAI1717system board is connected to LPT1 on anIBM-PCmade in the U.S. then the pcm17dem.ini should be modified to read

[PCM17DEM]

PCMIFADR = &H278

The pcm17dem.ini file can be modified using the windows program note pad.

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7

DEM-PCM1717

 

 

DEM-DAI1717SYSTEM BOARD INFORMATION

GENERAL SPECIFICATIONS

Table I lists the specifications for the DEM-DAI1717system board.

SPDIF Interface

Optical via Toslink

 

RCA with 75Ω impedance.

System Clock Frequency

256 times sampling frequency, fs

 

 

Digital Audio Interface

16 bits, Normal Format, MSB last

 

18 bits, Normal Format, MSB last

 

I2S 16 or 18 bits

THD+N

0.004% typical, with internal 20kHz Low

 

Pass Filter.

 

0.08% typical, direct out, with external

 

30kHz Low Pass Filter.

 

 

Dynamic Range

94dB typical, (EIAJ method, A-weighted

 

filter)

 

 

SNR

100dB typical, (EIAJ method, A-weighted

 

filter)

 

 

Maximum Output

2Vrms (using internal low pass filter out)

 

 

+VCC range

+4.5 to +5.5

+ICC

+60mA (no external load) to +120mA

±VS

±5V ~±15V

±IS

±15mA (no external load)

 

 

TABLE I. DEM-DAI1717General Specifications.

SPDIF INTERFACE OPTIONS

The DEM-DAI1717employs a SPDIF receiver chip. This receiver extracts 4 signals from a two wire signal that is interfaced to the board. The receiver can supply these four digital audio signals in up to eight different formats. Of these formats only three are useful or valid for the PCM1717. The output format is commanded by the setting switches S0, S1, and S2. Figure 7 shows the switches and resulting output configurations from the settings. Only the three configurations shown will produce valid outputs from the PCM1717E.

 

 

 

S0

 

 

S1

 

S2

 

 

 

L

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

H

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

S0

S1

S2

 

 

SPDIF Output Format

 

 

H

L

H

 

16 bits Normal Format MSB First

 

 

L

H

H

 

18 bits Normal Format MSB First

 

 

L

H

L

 

 

 

I2S 16 or 18 bits

 

 

 

 

 

 

 

 

 

 

 

 

 

FIGURE 7. SPDIF Interface Options.

JUMPER SETTINGS

The DEM-DAI1717system board has 5 jumpers blocks that allow the digital outputs from the SPDIF receiver chip to be connected to the PCM1717. The four jumpers that interconnect the four digital audio signals from the receiver chip are

®

installed by default. An optional ground connection can be made between the receiver chip and the PCM1717E. Refer to Figure 8 for the orientation of these jumpers.

JP

256fs LRCK BCK DATA GND

CS8412 PCM1717E

FIGURE 8. DEM-DAI1717Jumper Configuration.

MODE CONTROL SWITCH SETTINGS

The DEM-DAI1717system board uses 5 switches, labeled as S3, to select between software and hardware control and to provide settings for the hardware mode. When the DEMDAI1717 is to be used with the system software then it is necessary for all of the mode switches to be in the high or off position. Figure 9 shows the functions of all five of these switches.

 

 

 

 

 

DEM-DAI1717

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Low

 

Mute

 

Off

 

 

Off

 

 

Reset

 

Hardware

 

On

 

On

 

48kHz

 

 

44.1kHz

 

 

Off

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

De-Emphasis

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

High

 

Mute

 

44.1kHz

 

 

48kHz

 

 

Reset

 

Software

 

Off

 

Off

 

32kHz

 

 

32kHz

 

 

On

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ML

 

MC

 

 

MD

RSTB

 

Mode

 

 

FIGURE 9. DEM-DAI1717Mode Control Switch Settings.

PARALLEL PORT CONNECTIONS

Figure 10 shows the connections made between the parallel port connector and the pins on the PCM1717.

1

2

3

4

5

18

19

 

 

 

 

36

 

 

 

PARALLEL

PCM1717E

 

 

 

 

2

ML

 

 

 

 

3

MC

 

 

 

 

4

MD

 

 

 

 

5

RSTB

 

 

 

 

19 ~ 30

GND

FIGURE 10. DEM-DAI1717Parallel Port Connections.

 

DEM-PCM1717

8

 

HARDWARE CONNECTIONS FOR THE DEM-DAI1717

Hardware configuration of the DEM-DAI1717evaluation board consists of supplying a source of digital audio data, connecting the board to anIBM-PCparallel port, connecting the audio output to a speaker or measurement tool and supplying a source of power to the system board.

Digital Audio Source

Figure 11 shows the “schematic” drawing of the DEMDAI1717 evaluation board. There are a total of four connectors that must be used for the PCM1717 to reproduce digital audio data. Figure 12 details the parts location and orientation for the DEM-DAI1717evaluation board. The PCB layer design for the traces and ground planes used in theDEM-DAI1717system board are shown in Figure 13.

Digital Audio Input Data

The source of digital audio data is connected via the coax connector labeled as “CN3” or “COAX.” This port is used if the SPDIF digital audio data comes from a RCA connector.

SPDIF data can also be provided to the DEM-DAI1717system board via fiber optic connection. The “port” that is used for this form of data is connected to the U4 or OPT connection. The connection is made using a standard “Toslink” connector.

Power Connections

A 5 pin connector labeled CN1 is used to connect power to the DEM-DAI1717.A separate +5V supply is used for the SPDIF receiver chip and the PCM1717, labeled as +VCC.

The power connections +V

and –Vare used to provide for

S

S

the active filter op-amp,OPA2604. This amplifier should not be run at power supply voltages greater than ±15V. The

remaining pins are used for ground connections. These grounds are not isolated from each other electrically.

Analog or Audio Connections

The analog outputs of the PCM1717 are brought out directly through RCA jacks CN6 and CN7 for the left and right channel respectively. These outputs are referred to 1/2 of the VCC voltage, i.e. the output swings symmetrically about 2.5V for a 5V supply.

SOFTWARE DESCRIPTION

The PCM1717 demo software is used to control the internal register settings of the PCM1717 through a set of four windows. The main menu is brought up by clicking on the “D17CTRMK” icon in the applications folder.

MAIN MENU

Figure 14 shows the main menu that is brought up when the “D17CTRMK” icon is selected. This menu has three areas of interest. The “Execute” option allows the user to either reset the PCM1717 to its default power-onstate using the Reset command, or allows the user to exit from the PCM1717

software. The execute menu can be opened by either clicking on the “Execute” or by using the Alt-Ekey sequence. (All of the menus and commands can be activated by using the mouse and the left button or Alt key sequences). The Windows submenu(Alt-W)allows the Attenuation(Alt-A),Function(Alt-F),and Dataform(Alt-D)submenus to be opened. The function of these menus is explained in the next section.

The bottom of the PCM1717 Main or Control Menu contains the Hexadecimal value of the current contents of the PCM1717 four control or Mode Registers. For a more detailed description of these registers consult the product data sheet for the PCM1717E audio digital-to-analogconverter.

A Pass/Hold selection is available for all three of these control menus. When the Menu is in the Pass mode then commands are sent to the PCM1717 as various selection or options are selected immediately. When the Menu is in the Hold mode the changes are held in the software for the DEM-PCM1717until the menu is changed to the Pass Mode.

ATTENUATE MENU

The PCM1717 allows the user to command 255 steps of noiseless attenuation into each channel. The left and right channels can either be controlled together, i.e. equal attenuation of both channels, or independent control over each channel. Figure 15 shows the attenuation menu.

To change the attenuation or volume of a channel use the mouse pointer over the bar in the attenuation level menu for the desired channel, press and hold the left button and drag the bar to the desired level. Pressing the Hold selection in the Control Data section of the Attenuation Control Menu will change the Hold section to Pass, and the necessary register settings for the desired attenuation level will be passed to the PCM1717. The level or volume will change. (Note that if the Left and Right channels have been chosen to be equal from the Format Control menu, then only the Left channel Attenuation Level will be selectable.)

FORMAT CONTROL MENU

This menu allows the user to program the data input format, resolution, Left-Rightclock polarity, output format, and Attenuation formats for the PCM1717. This menu is composed of six submenus explained below. Figure 16 shows the default menu for this section.

FORMAT

This menu allows the PCM1717 to be programmed for either the standard or I2S format for incoming data to the DAC. The standard format is used when the incoming data is MSB aligned to theLeft-Rightclock or LRCK. The I2S format is used when the incoming data conforms the InterIC sound format. Refer to the product data sheet of the

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9

DEM-PCM1717

 

 

PCM1717E for a more detailed explanation of these formats. Selecting either of these formats is done by clicking on the Format window and selecting the desired format.

WIDTH

This menu controls the number of bits that the PCM1717 uses for digital audio conversion. The choices are either 16 or 18 bits.

LRCK

This menu selection allows the user to specify the polarity of the incoming digital audio data when respect to the left/right or sample clock. The choices allow the user to specify whether the low portion of the left/right clock is coincident with either the left or right channel data.

L-OUTANDR-OUT

These two menu selections allow the user to control the analog channels and formats through which the recovered digital data will be sent. The choices allow for either channel to be swapped or sent to the other channel allow the two channels to be summed together and the magnitude to be divided by two, mono, or allows either channel to be muted.

ATT CTRL

This menu controls whether the attenuation controls affect each channel individually or whether both channels are of equal volume.

PCM1717 FUNCTION CONTROL

This menu controls the De-emphasis,Infinite Zero Detection, and Operational Enable features of the PCM1717, as shown in Figure 18. These features are controlled by three submenus detailed below.

DeEMPH

This menu allows the selection of three de-emphasisfrequencies or allows thede-emphasisto be disabled.

IZD

This selection allows the user to turn on or off the infinite zero detection feature. Because this feature is either on or off there is no menu for its selection. Clicking on the box places an x in its selection and turns off the feature.

OPE

This selection allows the user to enable the operation of the PCM1717 this is equivalent to turning the PCM1717 on or off. As with the previous feature, this feature does not have a menu and the PCM1717 is enabled by clicking on the box and turning the PCM1717 on.

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DEM-PCM1717

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