® DEM-DAI1600 EVALUATION FIXTURE ● CENTRONICS CONNECTOR PROVIDED FOR CONNECTION TO A PC PRINTER PORT (Required for Demonstration Software) FEATURES ● COMPLETE EVALUATION PLATFORM FOR THE PCM1600 SIX-CHANNEL AUDIO D/A CONVERTER ● REQUIRES THREE POWER SUPPLIES: +5V, +15V AND –15V ● ON-BOARD REGULATOR GENERATES +3.3V FROM THE +5V SUPPLY ● DIGITAL AUDIO INTERFACE SUPPORTS S/PDIF INPUTS UP TO 96kHz FROM COMMERCIAL AUDIO EQUIPMENT AND AUDIO MEASUREMENT SYSTEMS (Both RCA and Optical Input Connectors Provided) ● DUAL IN-LINE HEADER SUPPORTS CONNECTION TO AN EXTERNAL AUDIO DSP OR DECODER ● SUPPORTS AN OPTIONAL EXTERNAL +3.3V SUPPLY DESCRIPTION The DEM-DAI1600 demonstration board provides an ideal platform for evaluating the performance and operation of the PCM1600 six-channel audio digitalto-analog converter. Demonstration software is included for controlling the PCM1600’s programmable functions. The D/A converter outputs are filtered and passed on to RCA jacks for connection to audio measurement equipment and commercial audio gear. A digital audio receiver allows connection to S/PDIF data streams, while an on-board connector provides an interface to audio Digital Signal Processors (DSP) and decoders. ● 2ND-ORDER LOW-PASS ACTIVE FILTERS FOR EACH DAC OUTPUT ● INCLUDES DEMONSTRATION SOFTWARE FOR WRITING AND READING PCM1600 CONTROL REGISTERS (Requires a PC with Microsoft Windows 3.1, 95, or 98) BLOCK DIAGRAM ML MC MDI RST MDO GND +VCC3 GND +5V –15V GND +15V 3.3V SW5 Opt Coax JUMPER Digital Audio Receiver and Logic +5V REG. 2nd-Order LPF OPA2134 SYSCLK SCKO BCLK LRCK DIN1 VOUT2 L/R ch PCM1600 Daughter Card L/R ch 2nd-Order LPF OPA2134 VOUT3 VOUT4 L/R ch DIN2 VOUT1 DIN3 2nd-Order LPF OPA2134 VOUT5 VOUT6 SW1 - SW3 Format Control 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/ • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132 ® © 1999 Burr-Brown Corporation LI-535 1 Printed in U.S.A. September, 1999 DEM-DAI1600 GENERAL DISCUSSION PC PRINTER PORT INTERFACE A Centronics connector is included so that the DEM-DAI1600 may be connected to a PC printer port. The demonstration software included with the DEM-DAI1600 uses this connection to write and read the PCM1600’s internal registers through the MDO, MDI, MC, and ML pins. POWER SUPPLIES The DEM-DAI1600 requires three external supplies: a +5V supply (VCC) is required for the PCM1600; a digital audio receiver (U3); and associated logic circuitry (U3, U4). An on-board regulator (Burr-Brown REG1117-3.3) is used to generate +3.3V from VCC, which is required by the PCM1600 and associated buffers (U5, U6). The output of the regulator can be disabled by a jumper (JP3) and an external +3.3V supply may then be provided at connector CN4. CONNECTORS CN1 is the main power supply connector. Connections for VCC, +VS, –VS, and power supply grounds are provided. The op amps used for the low-pass active filters (U50 through U52 ) require positive and negative power supplies. The +VS supply is typically +15V, with a maximum value of +18V and a minimum value of +5V. The –VS supply is typically –15V, with a minimum value of –18V and a maximum value of –5V. CN2 is the zero flag connector. Connector pins ZFLGA and ZFLG1 through ZFLG6 correspond directly to the zero flag output pins of the PCM1600. The power supplies used for VCC, +VS, and –VS should be well regulated and filtered. Switching power supplies may be used, but linear regulated supplies are recommended for optimal performance. All supplies should be rated for a minimum of 500mA of output current. CN4 is used to connect an optional external +3.3V power supply to the DEM-DAI1600. Typically, this connector is not used since an on-board regulator IC (U8) is used to generate the +3.3V supply. If an external +3.3V supply is used, remove the jumper at JP3. CN3 is a Centronics connector used to interface the DEMDAI1600 to a PC printer port. The +5V logic signals from the printer port are buffered by U6. CN10 through CN13 provide the connection to the PCM1600 daughter board. Figure 1 shows the electrical connections for CN10 through CN13. Figure 4 shows the daughter card schematic. The mapping between the daughter card connectors and CN10 through CN13 is shown in Table I. DIGITAL AUDIO INTERFACE The digital audio interface is provided by a Crystal CS8414 digital audio receiver (U3). The interface is used to receive a stereo, linear PCM, S/PDIF data stream from either an electrical or optical source. The electrical input is furnished by an RCA connector (PJ1), while the optical input is provided by a Toshiba TOSLINK optical receiver (OPT). S/PDIF streams are available from industry standard audio test systems (Audio Precision, Rhode & Schwarz), as well as commercial audio equipment (DVD, CD, and DAT players). The CS8414 outputs a stereo data stream at it’s SDATA pin. This may be used by any or all of the PCM1600’s three data inputs, DIN1 through DIN3. Jumper block JP2 is used to connect the CS8414 data output to the desired PCM1600 data input pins. DEM-DAI1600 CONNECTOR DAUGHTER CARD CONNECTOR CN10 CN1 CN11 CN2 CN12 CN3 CN13 CN4 TABLE I. Daughter Card Connector Mapping. OPT is the optical receiver input to the CS8414 digital audio receiver. PCM1600 DAUGHTER CARD PJ1 is the RCA connector used for shielded cable input to the CS8414 digital audio receiver. The PCM1600 package is soldered directly to a small printed circuit board, referred to as the “daughter card.” PJ2 is the audio output connector corresponding to the PCM1600’s VOUT1 output. The daughter card includes four male connectors which plug into four corresponding female connectors on the DEMDAI1600 board. The daughter card arrangement is used to provide the best possible dynamic performance, while allowing the PCM1600 to be easily interchanged with future multi-channel D/A products. PJ3 is the audio output connector corresponding to the PCM1600’s VOUT2 output. DAC OUTPUT FILTERS PJ6 is the audio output connector corresponding to the PCM1600’s VOUT5 output. PJ4 is the audio output connector corresponding to the PCM1600’s VOUT3 output. PJ5 is the audio output connector corresponding to the PCM1600’s VOUT4 output. Three dual op amps (Burr-Brown OPA2134 ) are included to provide 2nd-Order Butterworth low-pass filters for the DAC outputs. These filters are required to attenuate the out- ofband noise generated by the PCM1600’s delta-sigma D/A converters. PJ7 is the audio output connector corresponding to the PCM1600’s VOUT6 output. ® DEM-DAI1600 2 SWITCHES JUMPERS Switches SW1 through SW3 are used to select the audio data output format for the CS8414. Table II shows the output format selections that are used with the PCM1600. Jumper JP1 is used to select a non-inverted (NML) or inverted (INV) bit clock for the PCM1600. Table IV shows the proper settings for JP1 for the four input data formats shown in Table II. SW1 SW2 SW3 L L H H L H L H L L H L Jumper block JP2 is used to connect the digital audio receiver output data and clocks to the PCM1600 daughter DATA FORMAT 16-24 16-24 16-bit 18-bit Bit Left-Justified, MSB-First(1) Bit I2S(2) Standard Right-Justified, MSB-First(2) Standard Right-Justified, MSB-First(2) NOTE: (1) Jumper JP1 must be set to the INV position when using this format. (2) Jumper JP1 must be set to the NML position when using this format. TABLE II. Digital Audio Receiver Output Data Format Settings. MODE OF OPERATION L H Normal Reset(1) JP1 SELECTION INV NML NML NML TABLE IV. JP1 Jumper Selection for Audio Data Formats. Switch SW5 is used to set the state of the reset (RST) pin of the PCM1600. Table III shows the reset selections. CKS0 and CKS1 are unused and should be set to ‘L’. RST DATA FORMAT 16 - 24-Bit Left-Justified, MSB-First 16 - 24-Bit I2S 16-Bit, Standard Right-Justified, MSB-First 18-Bit, Standard Right-Justified, MSB-First card. The jumpers may be removed from JP2 to allow connection to an audio DSP or decoder. Figure 1 shows the electrical connections for JP2. Note that pins DIN1 through DIN3 include 10kΩ pull-down resistors, which may be used to set the data inputs to logic ‘0’ for testing zero detection functions and output cross talk performance. Jumper JP3 is used to enable or disable the on-board +3.3V regulator output. When the jumper is installed, the regulator is used as the +3.3V supply. When it is removed, an external supply, connected at CN4, may be used to supply the +3.3V. NOTE: (1) The RST pin of the PCM1600 is active LOW. Due to the demo board design, the ‘H’ selection closes the switch and connects RST to ground. The ‘L’ selection opens the switch and the RST pin is set to logic ‘1’ by an internal pull-up resistor. TABLE III. Reset (RST) Operation. SCHEMATICS Schematics for the DEM-DAI1600 are shown in Figures 1 through 4. Figure 1 shows the digital audio receiver, associated logic, and digital I/O connectors. Figure 2 shows the DAC low pass filters, while Figure 3 illustrates the power supply connections. Figure 4 shows the PCM1600 daughter card circuitry and connectors. ® 3 DEM-DAI1600 4 3 +VCC PJ1 C1 0.1µF R1 75Ω U1 TORX176 1 OPT COAX 2 4 5 6 + C4 10µF C3 0.01µF C2 0.01µF C5 0.1µF + C6 10µF +VCC M2 M1 M0 M3 14 13 12 11 10 9 8 7 6 5 4 3 2 1 6 2 M1 4 M2 U4 HC14 SW2 4 5 12 13 10 9 2 1 SEL CBL SW1 U2 HC32 +VCC 11 8 3 U CS12/FCK M3 SCK MCK RXN M2 FILT RXP FSYNC VA+ AGND DGND M0 VD+ M1 Cb/E2 C0/E0 ERF Cc/F0 Ca/E1 Ca/F2 SDATA Cd/F1 VERF C 3 U3 CS8414 JP1 TP1 M0 TP2 C8 0.1µF 1 M3 + C9 0.068µF R3 470Ω R4 470Ω SW4 PUSHSW D1 1S1500 + +VCC C11 10µF R2 47kΩ +VCC C7 10µF NML INV M2 +VCC M0 M1 SW3 U4 HC14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 RA1 10kΩ +VCC3 9 8 7 6 5 4 3 2 Y6 Y7 Y8 A6 A7 A8 OE2 OE1 Y5 Y4 Y3 Y2 Y1 A5 A4 A3 A2 A1 U5 VHC541 1 19 11 12 13 14 15 16 17 18 TP3 1 19 2 20 ML JP2 RST 9 27 10 28 R14 R13 R12 R11 R10 R9 R8(1) C13 10µF + +VCC3 MDO NOTE: (1) Resistors R8 - R14 are 22Ω. R7 10kΩ R6 10kΩ R5 10kΩ 3 21 4 22 5 23 6 24 MDI MC SW5 DSS203 7 25 8 26 +VCC3 19 9 8 7 6 5 4 3 2 1Y2 2A3 1Y3 2A2 1Y4 2A1 1A2 2Y3 1A3 2Y2 1A4 2Y1 CN2 1 11 12 13 14 15 16 17 18 CN13 OE1 2A4 2Y4 OE2 1Y1 1A1 DIN3 DIN2 DIN1 LRCK BCK GND SCKO SCKI GND VCC3 CN10 15 33 16 34 17 35 18 36 RST 11 29 12 30 13 31 14 32 U6 VHC244 CN3 NC GND VOUT6 VOUT5 GND VOUT4 VOUT3 GND VOUT2 VOUT1 GND CN11 VCC CN12 +VCC VCC DEM-DAI1600 GND ZFLG6 ZFLG5 ZFLG4 ZFLG3 ZFLG2 ZFLG1 ZFLGA ® NC MDO GND ZFLGA ZFLG1 ZFLG2 ZFLG3 ZFLG4 ZFLG5 ZFLG6 FIGURE 1. Main Schematic for the DEM-DAI1600. MDI MC ML C21 10µF + C22 10µF + C23 10µF + C24 10µF + C25 10µF + TP6 TP7 TP8 TP6 C20 10µF + + TP5 TP4 C15 10µF VOUT6 VOUT5 VOUT4 VOUT3 VOUT2 VOUT1 R56 15kΩ R50 8.2kΩ R62 1kΩ VOUT1 C50 2700pF R57 15kΩ R51 8.2kΩ R63 1kΩ VOUT2 C51 2700pF R58 15kΩ R52 8.2kΩ R64 1kΩ VOUT3 C52 2700pF R59 15kΩ R53 8.2kΩ R65 1kΩ VOUT4 C53 2700pF R60 15kΩ R54 8.2kΩ R66 1kΩ VOUT5 C54 2700pF R61 15kΩ R55 8.2kΩ R67 1kΩ VOUT6 C55 2700pF C56 270pF 2 3 U50 OPA2134 1 R68 100Ω PJ2 DAC1 AOUT C57 270pF 6 5 U50 OPA2134 7 R69 100Ω PJ3 DAC2 AOUT C58 270pF 2 3 U51 OPA2134 1 R70 100Ω PJ4 DAC3 AOUT C59 270pF 6 5 U51 OPA2134 7 R71 100Ω PJ5 DAC4 AOUT C60 270pF 2 3 U52 OPA2134 1 R72 100Ω PJ6 DAC5 AOUT C61 270pF 6 5 U52 OPA2134 7 R73 100Ω PJ7 DAC6 AOUT FIGURE 2. DAC Output Filters. ® 5 DEM-DAI1600 +VCC U8 REG1117-3.3 CN4 1 GND +VS –VS GND CN1 Out GND IN 1 2 2 3 5 4 3 2 1 GND 3.3V +VCC3 JP3 C81 10µF C89 100µF +VCC + + C83 0.1µF + C90 0.1µF GND C92 100µF C93 100µF + + +VCC –VS GND +VCC3 +VCC C80 0.1µF C86 0.1µF For U5, U6 +VS C82 0.1µF + C84 0.1µF For U2, U4 +VS GND –VS + C87 2.2µF + C88 2.2µF + C91 2.2µF C94 2.2µF For U51, U52, U53 + C95 2.2µF + C96 2.2µF For U51, U52, U53 VCC VCC GND NC NC MDO MDI MC ML RST FIGURE 3. Power Supply Connections. 25 AGND2 26 VCC2 27 AGND1 28 VCC1 29 VCC0 AGND0 30 NC 31 32 NC 33 34 VOUT1 ZEROA VOUT2 24 23 22 21 20 19 18 VOUT1 17 VOUT2 16 + GND 15 C5 10µF VOUT3 14 VOUT4 13 GND VOUT5 VOUT6 12 11 C7 0.1µF VOUT3 DATA3 VOUT4 VCOM2 VOUT5 DATA2 1 48 DATA1 VCOM1 10 47 DGND AGND6 VOUT6 46 PCM1600 VDD 9 DIN3 VCC6 VCC 45 U1 AGND DIN2 44 TEST 8 C1 0.1µF 43 ZERO6 DIN1 + C 2 10µF AGND5 7 LRCK LRCK 6 42 VCC5 ZERO5 BCK BCK 5 41 AGND4 ZERO4 GND SCLKO 4 40 VCC3 VCC4 ZERO3 SCKO SCLKI 3 39 + C 6 10µF AGND3 ZERO2 SCKI RST 2 38 ZERO1 37 GND MDO +VCC3 MDI 35 ML CN4 MC 36 CN1 GND CN2 FIGURE 4. PCM1600 Daughter Card. ® DEM-DAI1600 6 ZFLG6 ZFLG5 ZFLG4 ZFLG3 ZFLG2 ZFLG1 GND ZFLGA CN3 C3 0.1µF + C 4 10µF DEMONSTRATION SOFTWARE Software is provided with the DEM-DAI1600 to allow programming of the PCM1600’s internal registers. The software will operate on computers running Microsoft Windows 3.1, 95 or 98. The demo software requires that the PC printer port be connected to CN3 of the DEM-DAI1600 using a standard printer cable. The Execute menu includes three selections: Initialize, Reset, and Exit. Selecting Initialize will instruct the program to write all of the PCM1600’s internal registers with the default values. Selecting Reset will instruct the program to rewrite the PCM1600’s internal registers with the data currently selected in the application windows. Selecting Exit will close the application. Installation The demo software is distributed on a 3.5 inch floppy disk. There is a single folder on the disk, named “Dem1600.” This folder contains the application and all support files. The Window menu includes four selections: Attenuation, Operational Control, Function Control, and Register Read. The following sections provide an explanation of each window. To install the software on your computer, first create a new folder on your hard drive with an appropriate name (e.g., DEM1600, PCM1600, etc.). Then open the “Dem1600” folder on the installation floppy and copy all the files in it to your new folder. HOLD and PASS Each window has a button near the top. It’s labeled either HOLD or PASS. The current setting is toggled by clicking on the button. When set to HOLD, the settings in a window can be changed, but they will not be written to the register(s) until the OK button (which appears at the bottom of the window) is pressed. When set to PASS, setting changes made in a window are immediately written to the corresponding register(s). Open the configuration settings file named “Dem1600” with a text editor, such as Notepad. When the file is opened, find the following line: PCMIFADR = &h378 The &h378 indicates the printer port address that the demo software will use to communicate with the DEM-DAI1600. This address must be set to &h378, &h278, or &h3BC. Most PCs use &H378 as the default printer port address. If your printer port is not located at &h378, edit the address to match your computer’s port address. Attenuation Window The Attenuation window is used to set the digital attenuation registers internal to the PCM1600 and is shown in Figure 6. There is an attenuator for each of the six output channels, and each attenuator has its own independent register to control its attenuation level. In the Attenuation window, there is a slider for each attenuator register. Use the slider handle or the arrows at each end of the slider to adjust the attenuation level. The left and right arrow keys on the keyboard can also be used to adjust the level. Just to the right of each slider is a status display showing the current register setting (in decimal) and the corresponding attenuation level in decibels (dB) relative to the input signal level. Using the Demo Software Double click on the application file named “Dem1600.” A window will appear on your screen, as shown in Figure 5. There are two menus near the top of the window, named Execute and Window. FIGURE 5. Start Up Window. FIGURE 6. Attenuation Window. ® 7 DEM-DAI1600 Register Read Window The PCM1600 serial control interface includes register read capability. The Register Read window (or panel) allows the user to read the value of all PCM1600 registers by pressing a single button. The panel is shown in Figure 9. The Register Read panel provides a means to check for proper communications between the PC printer port and the DEM-DAI1600 by allowing the user to verify register write operations. Although the Attenuation window is used to set the level of the attenuation registers, the actual attenuators inside the PCM1600 will not be updated unless the attenuation load control, ATLD (in the Operational Control window) is set to LOAD. While ATLD is set to OFF, the attenuation registers are written to, but the attenuators are not updated. When ATLD is switched from OFF to LOAD, all attenuators will be updated simultaneously. Operational Control Window The Operational Control window (labeled DAC Operation) is used to program the soft mute (MUT1-6), DAC operation (DAC1-6), attenuation load (ATLD), attenuation rate (ATTS), and infinite zero detect mute (IZD) functions. The mute, DAC operation, and infinite zero mute functions are set using check boxes, as shown in Figure 7. The labels associated with the check boxes change from ON to OFF as the settings are toggled. The attenuation load and rate functions utilize pull-down menus to set ATLD to OFF or LOAD, and ATTS to 2/fS or 4/fS. For more information regarding these functions, please refer to the PCM1600 Product Data Sheet. FIGURE 8. Function Control Window. FIGURE 7. Operational Control Window. Function Control Window The Function window hosts the remainder of the PCM1600 control functions. All functions are programmed using pulldown menus, as shown in Figure 8. Functions that can be programmed by this window include: • SCLKO output enable (CLKE) and rate (CLKD) controls • De-Emphasis controls (DM12, DM34, DM56) and sample rate selection (DEM) • Audio Data Format (FORMAT) • Digital Filter Roll-Off (ROLL-OFF) These functions are described in detail in the PCM1600 Product Data Sheet. FIGURE 9. Register Read Window. ® DEM-DAI1600 8