DEM-PCM1717 DEM-PCM1717-1 DEM-DAI1717 ® EVALUATION FIXTURE DEM-DAI1717 FEATURES BLOCK DIAGRAMS ● DEM-PCM1717 Basic evaluation board for the PCM1717 requires an external audio processor for connection to digital audio source. EVALUATION SOFTWARE AND CONNECTOR Centronics Connector ● DEM-PCM1717-1 DEM-PCM1717 plus Windows evaluation software and connector. ● DEM-DAI1717 Evaluation board for the PCM1717 including evaluation software and Digital Audio Interface. 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: 910-952-1111 Internet: 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-Brown Corporation LI-475 1 DEM-PCM1717 Printed in U.S.A. July, 1996 BLOCK DIAGRAMS (CONT) DEM-PCM1717 Audio Data LRCK/BCK/DATA 256/384fs Lch Direct Out Lch Capacitive Out PCM1717 Control Data ML/MC/MD Rch Direct Out Rch Capacitive Out GND +VCC DEM-DAI1717 DAI DAC LPF Lch Direct Out COAX Lch Low Pass Out SPDIF CS8412 PCM1717 OPA2604 OPT Rch Low Pass Out Rch Direct Out GND –VS +VCC GND +VS The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes 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-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems. ® DEM-PCM1717 2 DEM-PCM1717 The DEM-PCM1717 is the basic evaluation fixture for the PCM1717 ∆Σ audio DAC. This fixture provides an easy way to connect power, data, and interface signals to the DAC. 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. 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). ML MC MD RSTB GND +VCC CN2 S1 4 CN1 CN3 5 CLKO VOL • C XTI VOL • D BCK VOR • D PCM1717E LRCK VOR • C DIN ZO GND GND R1 +VCC FIGURE 1. DEM-PCM1717 Block Diagram. HARDWARE DESCRIPTION DEM-PCM1717 Low Mute On Off 48kHz Off 44.1kHz Figure 3 shows the schematic diagram of the DEM-PCM1717 evaluation board. Reset Off Hardware On Off Figure 4 illustrates the PC board design and component placement for the DEM-PCM1717 evaluation 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 as DC-coupled (VOR-D, VOL-D) or ac-coupled (VOR-C, VOL-C). The DC coupled output is referred to ground, and the AC- coupled 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 pullup resistor, R1. This resistor is labeled R1 on the schematic and the board and a typical value is 4.7kΩ. De-Emphasis High Mute Off 44.1kHz 32kHz 48kHz 32kHz Reset On Software ML MC MD RSTB Mode FIGURE 2. DEM-PCM1717 Switch Settings. The crystal (U1) is not included. ® 3 DEM-PCM1717 GND DIN LRCK BCK XTI CLKO CN1 CS1 CS2 S1 ML/MUTE XTAL U1 MC/DM1 MD/DM0 PCM1717E 1 + 2 C4 2.2µF 3 4 5 6 7 C6 + 10µF 8 9 10 R1 XTI DGND VDD XTO CLKO ML/MUTE LRCIN MC/DM1 DIN MC/DM0 BACKIN RSTB ZERO MODE D/C_R D/C_L VOUTR VOUTL AGND VCC C8 + 10µF RSTB MODE 20 19 18 17 ML 16 MD 15 MC C5 10µF + 14 13 RSTB 12 GND 11 + C3 2.2µF + +VCC C2 0.1µF + C1 100µF CN2 C7 10µF CN3 GND ZO VOR-C VOR-D VOL-D VOL-C FIGURE 3. DEM-PCM1717 Schematic. ® DEM-PCM1717 4 XTAL, CS1, CS2, R1: Not Installed. FIGURE 4. DEM-PCM1717 Parts Layout and Trace Design. ® 5 DEM-PCM1717 DEM-PCM1717-1 PCM1717’s special functions are programmed via a 3-wire serial 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. This demo board kit consist of a DEM-PCM1717 hardware board, together with an interface cable, for connecting the DEM-PCM1717 to power and connecting the software control lines to an IBM-PC parallel port. DEM-PCM1717 also 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 the DEM-PCM1717-1. DEM-DAI1717 utilizes the parallel port of an IBM-compatible PC to implement the 3-wire serial programming interface. The evaluation software runs on Windows© Operating System. The DEM-DAI1717 evaluation 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 3wire 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 a 2nd-order filter for reduction of out-of-band noise. Figure 6 shows the block diagram of the DEM-DAI1717 system board. DEM-DAI1717 DEM-DAI1717 is a complete evaluation fixture, including an SPDIF receiver, PCM1717 and an analog post low-pass filter DEM-DAI1717 also includes evaluation software. PCM1717 contains features which can be programmed externally. These features include a 256-step digital attenuator, data interface format, word length, output format, etc. Refer to the PCM1717 data sheet for a complete description of these special functions. LRCK, BCK DIN, SYSCLK MC, MD, ML DEM-PCM1717 Left/Right Audio PC Centronics +5V, Ground Software FIGURE 5. DEM-PCM1717-1 Interface Connection. DAI-Settings Mode Settings S0, S1, S2 S3 Centronics Lch Direct Out SPDIF Optical V out L TORX 174 Lch Filtered Out DAI-Receiver CS8412 JP RCA - 75Ω 256fs LRCK DAC PCM1717 V out R BCK OPA2604 Low-Pass FIlter RCA: Connector Rch Filtered Out DATA Rch Direct Out GND +VCC –VS GND +VS FIGURE 6. DEM-DAI1717 Block Diagram. ® DEM-PCM1717 6 DEM-DAI1717 also 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. • 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. DEM-DAI1717 SYSTEM CONTENTS • DEM-DAI1717 Evaluation Board • DEM-DAI1717 Software on a 3.5" high density disc • DEM-DAI1717 Evaluation Board contains a SPDIF interface, an interface for the IBM-PC, and an external low pass filter for the DAC itself. • DEM-DAI1717 Software must be installed under the Windows version 3.1 or Windows 95. CONFIGURING THE PCM17DEM.INI FILE The DEM-PCM1717 software 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 the DEM-DAI1717 evaluation board the software must be configured for the parallel port to be used. The contents of the default pcm17dem.ini file is as follows: DEM-DAI1717 SYSTEM 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-PCM1717 Software and System Board [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-PC has three I/O addresses that are used for parallel or printer communications. The default address for the DEM-PCM1717 software is 3BC. If the port that is being used to control the DEM-DAI1717 system board is different from this default address then the 3BC address should be changed to that address. INSTALLING THE DEM-PCM1717 SOFTWARE It is recommended to install the DEM-PCM1717 software 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 a desk-top computer. Certain laptop PCs have non-standard parallel ports which may not be compatible with DEM-DAI1717. Typical port assignments are as follows: If the DEM-DAI1717 system board is connected to LPT1 on an IBM-PC made in the U.S. then the pcm17dem.ini should be modified to read 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-1717 PROGRAM The following procedure should be followed to create an Icon for starting the DEM-PCM1717 software. • 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. 3BC International Printer Port address 378 US LPT1 address 278 US LPT2 address [PCM17DEM] PCMIFADR = &H378 If the DEM-DAI1717 system board is connected to LPT1 on an IBM-PC made 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. ® 7 DEM-PCM1717 DEM-DAI1717 SYSTEM BOARD INFORMATION 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. GENERAL SPECIFICATIONS Table I lists the specifications for the DEM-DAI1717 system board. JP 256fs LRCK 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) BCK DATA GND CS8412 FIGURE 8. DEM-DAI1717 Jumper Configuration. MODE CONTROL SWITCH SETTINGS The DEM-DAI1717 system 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. TABLE I. DEM-DAI1717 General Specifications. DEM-DAI1717 SPDIF INTERFACE OPTIONS The DEM-DAI1717 employs 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 PCM1717E Low Mute On Off 48kHz Off 44.1kHz Reset Off Hardware On Off De-Emphasis High Mute Off 44.1kHz 32kHz 48kHz 32kHz Reset On Software ML MC MD RSTB Mode FIGURE 9. DEM-DAI1717 Mode Control Switch Settings. S2 PARALLEL PORT CONNECTIONS L Figure 10 shows the connections made between the parallel port connector and the pins on the PCM1717. H S0 S1 S2 SPDIF Output Format H L L L H H H H L 16 bits Normal Format MSB First 18 bits Normal Format MSB First I2S 16 or 18 bits 1 3 4 18 5 19 FIGURE 7. SPDIF Interface Options. JUMPER SETTINGS The DEM-DAI1717 system 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 36 PARALLEL PCM1717E 2 3 4 5 19 ~ 30 ML MC MD RSTB GND FIGURE 10. DEM-DAI1717 Parallel Port Connections. ® DEM-PCM1717 2 8 HARDWARE CONNECTIONS FOR THE DEM-DAI1717 software. The execute menu can be opened by either clicking on the “Execute” or by using the Alt-E key 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. Hardware configuration of the DEM-DAI1717 evaluation board consists of supplying a source of digital audio data, connecting the board to an IBM-PC parallel 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-DAI1717 evaluation board. The PCB layer design for the traces and ground planes used in the DEM-DAI1717 system board are shown in Figure 13. 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-analog converter. 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-PCM1717 until the menu is changed to the Pass Mode. 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-DAI1717 system 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. 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. 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 +VS and –VS are used to provide for 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. 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.) 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. FORMAT CONTROL MENU This menu allows the user to program the data input format, resolution, Left-Right clock 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. 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. FORMAT 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-on state using the Reset command, or allows the user to exit from the PCM1717 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 the Left-Right clock or LRCK. The I2S format is used when the incoming data conforms the InterIC sound format. Refer to the product data sheet of the ® 9 DEM-PCM1717 PCM1717 FUNCTION CONTROL 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. 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. WIDTH This menu controls the number of bits that the PCM1717 uses for digital audio conversion. The choices are either 16 or 18 bits. DeEMPH This menu allows the selection of three de-emphasis frequencies or allows the de-emphasis to be disabled. 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. IZD L-OUT AND R-OUT 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. 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. 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. ® DEM-PCM1717 10 FIGURE 11. DEM-DAI1717 Schematic. 11 ® DEM-PCM1717 OPT 4 5 COAX 2 3 U4 CN3 6 TORX174 C10 0.1µF C9 10µF + 1 C11 0.047µF R1 75Ω C12 0.47µF C5 + 10µF C6 0.1µF 26 3 14 13 12 11 10 9 8 7 CS12/FCK SCK FSYNC FXN PXP DGND VD SEL M3 M2 MCK FRT AGND VA 15 16 17 18 19 20 21 22 23 24 MO M1 5 6 25 4 SDATA 27 2 CC/FO 28 U1 CS8412CP 1 C7 0.1µF C13 0.047µF R2 1kΩ C8 10µF + JP GND BCK DATA LRCK XTI S2 S1 S0 +VCC R15 C18 0.1µF 1 + 10 9 8 7 6 5 4 3 2 XTI ML XTO VOUTL VCC D/C_L VOUTR AGND D/C_R RSTB MODE ZERO MC/DM1 MC/DM2 ML/MUT CLKO 11 12 13 14 15 16 17 18 19 20 MODE RSTB MD MC BACKIN DIN LRCIN VDD DGND PCM1717E S3 R14 100Ω R13 100Ω R12 100Ω C17 0.1µF C20 10µF + + C16 10µF 36 R11 100Ω 18 1 19 C21 10µF C19 + 10µF CN2 + C23 10µF + C22 10µF +VCC GND R4 5.6kΩ –VS C25 2700pF R6 10kΩ R8 3.9kΩ C24 2700pF GND C27 330pF C26 330pF +VS C3 C4 100µF 100µF + + R5 10kΩ R7 3.9kΩ +VCC C2 0.1µF + C1 100µF R3 5.5kΩ CN1 –VS +VS C15 0.1µF R9 100Ω R10 100Ω 1/2U3 OPA2604 1/2U3 OPA2604 C14 0.1µF CN5 Rch Direct Out CN4 Rch Filtered Out CN5 Lch Direct Out CN4 Lch Filtered Out FIGURE 12. DEM-DAI1717 Parts Layout. ® DEM-PCM1717 12 FIGURE 13. DEM-DAI1717 PCB Design. ® 13 DEM-PCM1717 PCM1717 Control Execute (E) Execute (E) Reset (R) Window (W) Exit (X) Mode Register Register 0 01FFH Register 1 01FFH Register 2 0000H Register 3 0090H Window (W) Attenuate (A) Function (F) Dataform (D) Control Data Control Data HOLD Attenuate Level 0.00 dB Right DeEmph Format Width LRCK OFF Standard 16 bit Low = R L-Out R-Out Att Ctrl L-In R-In L<>R Mute OFF step 255 IZD OFF Output Format OPE ON 0.00 dB CLOSE CLOSE CLOSE FIGURE 14. Demo Software Main Menu. PCM1717 Attenuate Control Control Data HOLD Attenuate Level Left step 255 0.00 dB step 255 0.00 dB Right CLOSE Attenuate Level Left step 81 –10.00 dB step 81 –10.00 dB Right FIGURE 15. Demo Software Attenuation Menu. ® DEM-PCM1717 HOLD Input Format Functional Condition Left step 255 Control Data HOLD 14 PCM1717 Format Control Control Data PCM1717 Attenuate Control HOLD Control Data Input Format HOLD Functional Condition Format Width LRCK DeEmph Standard 16 bit Low = R OFF L-Out R-Out Att Ctrl Mute OFF L-In R-In L<>R Output Format IZD OFF CLOSE Format CLOSE Audio Data Format Select DeEmph Standard De-Emphasis Control OFF Standard OFF IIS Width OPE ON 48.0kHz 44.1kHz 32.0kHz Input Audio Data Bit Select 16 bit 16 bit 18 bit LRCK Polarity of LRCKIN (pin 4) Select Low = R Mute OFF Left and Right DACs Soft Mute IZD OFF Internal Zero Detection Circuit Control OPE ON Left and Right DACs Operation On/Off Control Low = R Low = L L-Out Analog Output Mode Select L-In (Left-Channel) Mute FIGURE 17. Demo Software Function Menu. L-In R-In (L+R)/2 R-Out Analog Output Mode Select R-In (Right-Channel) Mute L-In R-In (L+R)/2 Att Ctrl Attenuator Control L == R L <> R L=R FIGURE 16. Demo Software Format Menu. ® 15 DEM-PCM1717