w WM8766-EV1M WM8766 Evaluation Board User Handbook INTRODUCTION The WM8766 is a 24-bit, 192kHz 6-Channel DAC. This evaluation platform and documentation should be used in conjunction with the latest version of the WM8766 datasheet. The datasheet gives device functionality information as well as timing and data format requirements. This evaluation platform has been designed to allow the user ease of use and give optimum performance in device measurement as well as providing the user with the ability to listen to the excellent audio quality offered by the WM8766. GETTING STARTED PACKING LIST The WM8766 Evaluation Kit contains: • 1 WM8766-EV1B Evaluation Board • 2 WM8766-EV1S 3.5” floppy disks containing control software • This manual -1 WM8766-EV1M CUSTOMER REQUIREMENTS Minimum customer requirements are: • D.C. Power supply of +12V and -12V • D.C. Power supply of +2.7V to +5.5V • PC and printer cable (for software control) Minimum spec requirements are: • Win95/98/NT/2000/XP • 486 Processor DAC Signal Path Requires: • Digital coaxial or optical data source • 1 set of active stereo speakers WOLFSON MICROELECTRONICS plc www.wolfsonmicro.com November 2003, Rev 1.2 Copyright 2003 Wolfson Microelectronics plc WM8766-EV1M EVALUATION BOARD OPERATION POWER SUPPLIES Using appropriate power leads with 4mm connectors, supplies should be connected as described in Table 1. REF-DES SOCKET NAME J1 +5V SUPPLY +5V J3 DVDD +2.7V to +3.6V J4 AVDD +2.7V to +5.5V J6 -12V -12V J7 +12V +12V J2 DGND 0V J5 AGND 0V Table 1 Power Supply Connections The DGND and AGND connections may be connected to a common GND on the supply with no reduction in performance. Note: Refer to WM8766 datasheet for limitations on individual supply voltages. Important: Exceeding the recommended maximum voltage can damage EVB components. Under voltage may cause improper operation of some or all of the EVB components. BOARD FUNCTIONALITY There are three options for inputting digital data into the WM8766 evaluation board. There is a coaxial input (J10) via a standard phono connector or an optical input (U1) via a standard optical receiver module. A direct digital input is also available via one side of a 2x8 pin header (H1). The analogue outputs of the board are via phono connectors J21 (VOUT2R), J28 (VOUT2L), J14 (VOUT3R), J18 (VOUT3L), J9 (VOUT4R), J12 (VOUT4L). All WM8766 device pins are accessible for easy measurement via the 1x14 pin headers (J16 and J25) running up each side of the device. Level-shift IC (U7) is used to shift the fixed +5V digital input from the CS8427 (U3) down to the same level as DVDD and vice-versa. BOARD INPUT When used in Slave Mode digital clock signals must be applied to the WM8766. A digital (AES/EBU, UEC958, S/PDIF, EIAJ CP340/1201) signal input may be applied to the coaxial input (J10), or the optical input (U1), allowing the CS8427 (U3) to generate the necessary clocks. A direct digital input is also available via one side of a 2x8 pin header (H1) data must be input in one of the WM8766 supported formats - see datasheet. Note: When used in Master Mode, an SPDIF signal must still be applied to phono connector J10. This input signal is used to allow correct operation of the CS8427 as well as being used to generate the MCLK for the WM8766. BOARD OUTPUT The WM8766 eval board can also be used with the 8 channel WM8768. As a result, the board has decals for 4 stereo channels (VOUT1-4). Since the WM8766 provides 3 stereo channels, VOUT1L/R are left unpopulated on the board. Instead, VOUT1L/R of the chip are output on VOUT2L/R of the eval board. Similarly, VOUT2L/R and VOUT3L/R of the chip are output on VOUT3L/R and VOUT4L/R of the board respectively (see Table 5). There are 6 analogue signal output phono connectors starting at VOUT2L/R: J21 (VOUT2R), J28 (VOUT2L), J14 (VOUT3R), J18 (VOUT3L), J9 (VOUT4R) and J12 (VOUT4L). Each of these outputs is passed through a post DAC active low-pass filter. w Rev 1.2 November 2003 2 WM8766-EV1M INTERFACES KEY J1 J2 J4 J3 J5 J6 J7 1 0 1 1 J8 VOUT4R 2 2 4 6 8 10 12 14 16 12 10 8 6 4 2 11 9 7 5 3 1 4 OPEN 3 1 3 5 7 9 11 13 15 1 5 6 J11 SW1 VOUT4L 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 J13 VOUT3R 1 2 3 J15 1 1 2 1 H1 J17 J16 VOUT3L 1 SW2 1 J19 J20 1 J23 1 J24 1 VOUT2R 1 J22 LNK1 J27 LNK2 1 LNK4 LNK5 LNK6 LNK7 1 VOUT2L J25 1 1 1 1 Figure 1 Interfaces HEADERS H1 SIGNAL 1/2 DACDAT 3/4 GND 5/6 DACLRC 7/8 GND 9/10 DACBCLK 11/12 GND 13/14 DACMCLK_IN 15/16 GND J16 WM8766 PIN NAME J19 WM8766 PIN NAME 1 1 MODE 1 15 TESTREF 2 2 MCLK 2 16 VREFN 3 3 BCLK 3 17 VREFP 4 4 LRCLK 4 18 VMID 5 5 DVDD 5 19 NC 6 6 DGND 6 20 NC 7 7 DIN1 7 21 VOUT1L 8 8 DIN2 8 22 VOUT1R 9 9 DIN3 9 23 VOUT2L 10 10 DNC 10 24 VOUT2R 11 11 ML/I2S 11 25 VOUT3L 12 12 MC/IWL 12 26 VOUT3R 13 13 MD/DM 13 27 AGND 14 14 MUTE 14 28 AVDD Table 2 Headers w Rev 1.2 November 2003 3 WM8766-EV1M LINKS LINKS AND JUMPERS DESCRIPTION LNK1 (Master/Slave) Pins 1 and 2 SHORT – Master Mode Pins 2 and 3 SHORT – Slave Mode LNK2 (Mute) Pins 1 and 2 SHORT – MUTE On Pins 2 and 3 SHORT – MUTE Off LNK4 (MD/DM) Pins 1 and 2 SHORT – DEEMPH Activated Pins 2 and 3 SHORT – DEEMPH De-activated LNK7 (MODE) Pins 1 and 2 SHORT – Hardware Mode Pins 2 and 3 SHORT – Software Mode LNK6 (MC/IWL) [Hardware Mode Only] LNK6 LNK5 FORMAT 2-3 2-3 24-bit Right Justified 2-3 1-2 20-bit Right Justified 1-2 2-3 16-bit I2S 1-2 1-2 24-bit I2S OPEN - No Power to AVDD (used for current measurements) SHORT - Power to AVDD LNK5 (ML/I2S) [Hardware Mode Only] J15 (AVDD) J19 (DVDD) OPEN - No Power to DVDD (used for current measurements) SHORT - Power to DVDD J22 Pins 1 and 2 SHORT – Connect DIN1 to DACDAT Pins 2 and 3 SHORT – Connect DIN1 to GND J23 Pins 1 and 2 SHORT – Connect DIN2 to DACDAT Pins 2 and 3 SHORT – Connect DIN2 to GND J24 Pins 1 and 2 SHORT – Connect DIN3 to DACDAT Pins 2 and 3 SHORT – Connect DIN3 to GND J8, J11, J13, J17, J20, J27 OPEN - VOUT signals are AC coupled before the LPF SHORT - VOUT signals are not AC coupled before the LPF Table 3 Links SWITCHES SWITCH SW2 SW1 (DATA FORMAT) DESCRIPTION After an input data format change has been made using SW2, the CS8427 will only latch the new settings after SW1 has been pressed and released. 1 1 1 1 2 0 0 0 3 0 0 0 4 1 0 0 5 0 0 0 6 0 1 0 DATA FORMAT I2S Compatible 24-bit Right Justified Left Justified Table 4 Switches ANALOGUE OUTPUTS CHIP BOARD VOUT1L/R VOUT2L/R VOUT2L/R VOUT3L/R VOUT3L/R VOUT4L/R Table 5 Analogue Outputs w Rev 1.2 November 2003 4 WM8766-EV1M WM8766 OPERATION HARDWARE MODE To operate the WM8766 in hardware mode, the jumper on link LNK7 (MODE) must short pins 1 and 2 together. The 3-pin links on the board (LNK1, 2, 4, 5, 6) then become the active source for changing the device functions. The diagram shown in Figure 2 used with the settings specified in Table 6 will assist in setting the WM8766-EV1B into a known state. This is to ease the initial use of the WM8766 until the user becomes familiar with device operation. +5V DGND +2.7V to +3.6V +2.7V to +5.5V AGND -12V +12V J1 J2 J3 J4 J5 J6 J7 1 0 1 1 J8 VOUT4R 2 4 OPEN 3 1 5 6 VOUT4L J11 SW1 1 J13 VOUT3R J15 1 1 H1 J17 J16 VOUT3L 1 SW2 1 J19 J20 1 J23 1 J24 1 VOUT2R 1 J22 LNK1 J27 1 LNK7 LNK2 1 LNK4 LNK5 LNK6 1 VOUT2L J25 1 1 1 Figure 2 Recommended DAC Setup LINKS AND JUMPERS H1 DESCRIPTION All jumpers in place LNK1 (Master/Slave) Pins 2 and 3 SHORT - Slave Mode LNK2 (MUTE) Pins 2 and 3 SHORT – MUTE off LNK4 (MD/DM) Pins 2 and 3 SHORT – No De-emphasis LNK7 (MODE) Pins 1 and 2 SHORT – Hardware Mode LNK6 (MC/IWL) LNK5 (ML/I2S) LNK6 1-2 LNK5 1-2 FORMAT 24-bit I2S J15 (AVDD) SHORT - Power to AVDD J19 (DVDD) SHORT - Power to DVDD J22 Pins 1 and 2 SHORT – Connect DIN1 to DACDAT J23 Pins 1 and 2 SHORT – Connect DIN2 to DACDAT J24 Pins 1 and 2 SHORT – Connect DIN3 to DACDAT J8, J11, J13, J17, J20, J27 OPEN - VOUT signals are AC coupled before the LPF Table 6 DAC Hardware Jumper Setup (Slave Mode) Please refer to Table 3 of this document and the WM8766 datasheet for further details on device configuration in hardware mode. w Rev 1.2 November 2003 5 WM8766-EV1M SOFTWARE CONTROL To operate the WM8766 in SPI (3-wire) software mode, the jumper on link LNK7 (MODE) must short pins 2 and 3 together. The SPI interface then becomes active on device pins 11(ML/I2S), 12(MC/IWL) and 13(MD/DM). The serial interface on the board can be connected to a PC via the printer port or any other standard parallel port. The port used can be selected through the software provided. The software supplied with this kit gives the user access to all the possible features provided by the WM8766. Please refer to the WM8766 datasheet for full details of the serial interface timing. ML/I2S MC/IWL B15 MD/DM B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 Figure 3 SPI Serial Interface REGISTER B15 B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 R0(00h) 0 0 0 0 0 0 0 UPDATE LDA1[7:0] 011111111 R1(01h) 0 0 0 0 0 0 1 UPDATE RDA1[7:0] 011111111 R2(02h) 0 0 0 0 0 1 0 PL[8:5] IZD PHASE[8:6] DACIWL[5:4] B3 B2 B1 B0 PDWN DEEMP MUTE All DAC ALL DAC All DAC ATC DACBCP DEFAULT 100100000 DACFMT[1:0] DACLRP 000000000 R3(03h) 0 0 0 0 0 1 1 R4(04h) 0 0 0 0 1 0 0 UPDATE LDA2[7:0] 011111111 R5(05h) 0 0 0 0 1 0 1 UPDATE RDA2[7:0] 011111111 R6(06h) 0 0 0 0 1 1 0 UPDATE LDA3[7:0] 011111111 R7(07h) 0 0 0 0 1 1 1 UPDATE RDA3[7:0] 011111111 R8(08h) 0 0 0 1 0 0 0 UPDATE MASTDA[7:0] 011111111 R9(09h) 0 0 0 1 0 0 1 DEEMP[8:6] R10(0Ah) 0 0 0 1 0 1 0 DACRATE[8:6] R12(0Ch) 0 0 0 1 1 0 0 0 0 R15(0Fh) 0 0 0 1 1 1 1 0 0 R31(1Fh) 0 0 1 1 1 1 1 DMUTE[5:3] DZFM[2:1] ZCD 000000000 0 010000000 DACMS PWRDN ALL MPD 0 0 0 0 0 0 000000000 0 MPD 0 0 0 0 0 00000000 DACD[3:1] RESET 000000000 Table 7 Mapping of Program Registers Please refer to the WM8766 datasheet for full details of the register features. Important: It must be noted that the CS8427 SPDIF decoder IC will only work at a rate of 256fs. This will limit the sample rates that may be set using the WM8766 unless an external source is used supplying signals directly to the relevant pins of header H1. w Rev 1.2 November 2003 6 WM8766-EV1M SERIAL INTERFACE SOFTWARE DESCRIPTION SOFTWARE INSTALLATION There are 2 floppy disks supplied with this evaluation kit. To install the software: 1. Insert disk 1 2. Select the ‘Start’ button on the Windows task bar and the ‘Run…’ option. 3. Type “A:\setup” and then press OK. 4. Follow the on-screen instructions SOFTWARE OPERATION The WM8766 software can be configured for use with the WM8796, WM8798 and WM8768. Select the WM8766 in the drop down menu labelled ‘Select device’. Due to the many features offered by the WM8766 the software has been split into 3 different panels. This eases the complexity of the software making each panel less busy, the panels have also been grouped so that it makes it simple to control each section of the device. The main menu panel shown in Figure 4 is used to call up the other panels as well as offering a number of pull-down menus. Figure 4 Software Menu Panel w Rev 1.2 November 2003 7 WM8766-EV1M The ‘Submit’ button will submit values to every register of the WM8766. The ‘Device Reset’ button writes to the reset register R31 but does not reset the control panel values. If the previous values are to be resubmitted then the ‘Submit’ button should be pressed, if the user would like to start afresh then the ‘Reset Software Panel Settings’ button should also be pressed. Pressing this button does not write to the device, it only resets the panel settings to their default state. Left clicking on the Wolfson logo will open the PCs default web browser and go top the Wolfson Microelectronics website (‘www.wolfsonmicro.com’). Pressing the ‘Submit Master Control’ button will only submit changes made to the Master Power Down switch. WRITING TO REGISTERS Two methods are provided to write to the WM8766 registers: 1. By pressing buttons ‘DAC SETUP CONTROL’ and ‘DAC VOLUME CONTROL’ on the software menu panel (Figure 4), further panels control will open (see Figure 6 and Figure 7). These panels display sliders and buttons that provide a visual interface to the registers of the WM8766. For example when the volume sliders for DAC1 on the DAC VOLUME CONTROL panel are used, they update the settings in registers R0 and R1 accordingly. 2. On the software control panel itself, there is a map of all registers and their current settings. Registers can be directly set from this panel. Any changes made in the ‘DAC SETUP CONTROL’ and ‘DAC VOLUME CONTROL’ panels will be reflected in the register map on the software control panel and vice versa. w Rev 1.2 November 2003 8 WM8766-EV1M TEST SETUP FOR STANDARD DAC OPERATION For the standard ‘DAC Setup’ the device is setup to receive data via the SPDIF_In to the DAC, after conversion the DAC outputs to VOUT1/2/3. Table 8 lists the required board settings to allow this signal path to become active in 24-bit, I2S input data format. This is to ease the initial use of the WM8766 until the user becomes familiar with both device and software operation. +5V DGND +2.7V to +3.6V +2.7V to +5.5V AGND -12V +12V J2 J3 J4 J5 J6 J7 J1 1 0 1 1 J8 VOUT4R 2 4 OPEN 3 1 5 6 VOUT4L J11 SW1 1 J13 VOUT3R J15 1 1 H1 J17 J16 VOUT3L 1 SW2 1 J19 J20 1 J23 1 J24 1 VOUT2R 1 J22 LNK1 J27 1 LNK7 LNK2 1 LNK4 LNK5 LNK6 1 VOUT2L J25 1 1 1 Figure 5 Recommended DAC Setup LINKS AND JUMPERS H1 DESCRIPTION All jumpers in place LNK1 (Master/Slave) Pins 2 and 3 SHORT - Slave Mode LNK2 (MUTE) Pins 2 and 3 SHORT – MUTE off LNK4 (MD/DM) No Effect LNK7 (MODE) Pins 2 and 3 SHORT – Software Mode LNK6 (MC/IWL) No Effect LNK5 (ML/I2S) No Effect J15 (AVDD) SHORT - Power to AVDD J19 (DVDD) SHORT - Power to DVDD J22 Pins 1 and 2 SHORT – Connect DIN1 to DACDAT J23 Pins 1 and 2 SHORT – Connect DIN2 to DACDAT J24 Pins 1 and 2 SHORT – Connect DIN3 to DACDAT J8, J11, J13, J17, J20, J27 OPEN - VOUT signals are AC coupled before the LPF Table 8 DAC Software Jumper Setup (Slave Mode) w Rev 1.2 November 2003 9 WM8766-EV1M DAC CONTROL Figure 6 DAC Control The DAC Control panel is used to control the many DAC related features of the WM8766. Pressing the ‘DAC Submit’ button will cause the settings shown on this panel to be written to the WM8766. A full device register write is not sent. w Rev 1.2 November 2003 10 WM8766-EV1M DAC ATTENUATION CONTROL Figure 7 DAC Attenuation Control The DAC Attenuation Control panel is used to control both the digital DAC volume of the WM8766. The volume sliders update in ‘real’ time (i.e. the ‘DAC Attenuation Submit’ button does not have to be pressed to update the output volume level) but will only have an effect on the output if the UPDATEL/R bits are set. Once changes are made to the UPDATEL/R bits, the ‘DAC Attenuation Submit’ button must be left clicked for the change to take effect. Pressing the ‘DAC Attenuation Submit’ button will cause the settings shown on this panel to be written to the WM8766. A full device register write is not sent. w Rev 1.2 November 2003 11 WM8766-EV1M WM8766-EV1B SCHEMATIC Figure 8 Functional Diagram Figure 9 SPDIF Input / Output Interface w Rev 1.2 November 2003 12 WM8766-EV1M Figure 10 Software Control Figure 11 Level Shift w Rev 1.2 November 2003 13 WM8766-EV1M Figure 12 WM8766 w Rev 1.2 November 2003 14 WM8766-EV1M Figure 13 Analogue Output w Rev 1.2 November 2003 15 WM8766-EV1M Figure 14 Power w Rev 1.2 November 2003 16 WM8766-EV1M WM8766-EV1B PCB LAYOUT Figure 15 Top Layer Silkscreen w Rev 1.2 November 2003 17 WM8766-EV1M Figure 16 Top Layer w Rev 1.2 November 2003 18 WM8766-EV1M Figure 17 Bottom Layer w Rev 1.2 November 2003 19 WM8766-EV1M Figure 18 Bottom Layer Silkscreen w Rev 1.2 November 2003 20 WM8766-EV1M WM8766-EV1B BILL OF MATERIAL REFERENCE DESCRIPTION Phono Socket PCB mount RED J9, J14, J21 Phono Socket PCB mount YELLOW J10 Phono Socket PCB mount WHITE J12, J18, J28 74ALVC164245 16 Bit Dual Supply Bus Transceiver SSO U7 DIL Switch 6-Way Rocker SW1 36-way Centronics/IEE488 PCB mountable Connector J29 B3F1000 SPNO PCB mount switch SW2 47k 1206 SMD chip 4 resistor array 5% 0.063W R4. R10, R12 1.32mm PCB Test Terminal BLACK TP1-7, TP11 1.32mm PCB Test Terminal RED TP8-10 0.01uF 0805 SMD Ceramic Capacitor 50V X7R C20 0.1uF 0805 SMD Ceramic Capacitor 50V X7R C1, C3, C6, C8, C10, C13, C14, C21, C28, C35, C37, C39, C48, C49, C51, C52, C56, C57, C60, C61, C62, C63, C68, C69, C74, C75, C76, C77 0.47uF 0805 SMD Ceramic Capacitor 16V X7R C34 74HC157 Quad 2-Input Mux SO U9 4mm Non-Insulated Panel Socket 16A J1-7 1x2 PCB Pin Header 0.1" VERTICAL J8, J11, J13, J15, J17, J19, J20, J27 1x3 PCB Pin Header 0.1" VERTICAL J22, J23, J24 2x8 2.54mm pitch PCB Pin Header VERTICAL H1 3.3uH 1210 Surface Mount Inductor '1210A series' L7 MC33078 Low Noise Dual Op-Amp SO U2, U4, U8 0.047uF 0805 SMD Ceramic Capacitor 25V X7R C29 100uF 8 Dia 3.5 pitch Oscon Through Hole Cap. 10V 20% C58 10uF 6.3 Dia 2.5 pitch Oscon Through Hole Cap. 16V 20% C23, C31, C38, C53, C64 DS1813 5V active Low Power-On-Reset chip SOT U5 220pF 0805 SMD Ceramic Capacitor 50V NPO C15, C26, C30, C42, C50, C67 680pF 0805 SMD Ceramic Capacitor 50V NPO C17, C24, C32, C40, C54, C65 1nF 0805 SMD Ceramic Capacitor 50V NPO C18 1nF 0805 SMD Ceramic Capacitor 50V NPO C25, C33, C41, C55, C66 TN0200T N- Channel MOSFET SOT23 Q9, Q11, Q12 0R 0603 SMD chip resistor 1% 0.063W R38, R39, R45, R48 0R 0805 SMD chip resistor 1% 0.1W R47, R49, R59, R66, R71, R79 0R 1206 Resistor on 1210 Inductor site L1-5 390R 0805 SMD chip resistor 1% 0.1W R21 560R 0805 SMD chip resistor 1% 0.1W R78 1K2 0805 SMD chip resistor 1% 0.1W R57, R60, R69 1K8 0805 SMD chip resistor 1% 0.1W R6, R17, R23, R31, R41, R53 4K7 0805 SMD chip resistor 1% 0.1W R8, R11, R14, R19, R25, R27, R28, R33, R43, R46, R50, R55, R58, R67, R70 10K 0805 SMD chip resistor 1% 0.1W R5, R16, R22, R30, R40, R52, R56 100K 0805 SMD chip resistor 1% 0.1W R20 49R9 0805 SMD chip resistor 1% 0.125W R9, R15, R26, R29, R44, R51 7K5 0805 SMD chip resistor 1% 0.125W R7, R18, R24, R32, R42, R54 47uH 1210 Surface Mount Inductor 'PA series' L6 10uF 6.3 Dia 2.5 pitch Oscon Through Hole Cap. 25V 20% C2, C4, C5, C7, C9, C36, C47, C59 75R 0805 SMD chip resistor 1% 0.125W R13 w Rev 1.2 November 2003 21 WM8766-EV1M REFERENCE DESCRIPTION 10uF 10V SMD Tantalum Capacitor case A C27 HSMY-C670 0805 SMD Chip LED YELLOW D1 TORX176 Digital Audio Optical Receiver U1 1x14 2.54mm pitch PCB Pin Header VERTICAL J16, J25 JSK9-16-G0 PCB 1x3 Jumper Switch 0.1" Center-off VERTICAL LNK1, 2, 4, 4, 5, 6, 7 CS8427 96KHz Audio Transceiver U3 WM8766 24-bit; 192kHz 8 channel DAC in 28-pin SO package U6 Table 9 Bill of Materials w Rev 1.2 November 2003 22 WM8766-EV1M APPENDIX EXTERNAL DSP CONNECTION TO THE WM8766-EV1B The WM8766-EV1B evaluation board has been designed to allow it to be easily connected to an external DSP platform with error free operation. The following information is provided to ease the connection process and ensure that all signals sent and received by the WM8766-EV1B are reliable and at the correct voltage levels. AUDIO INTERFACE CONNECTIONS It is recommended that twisted pair (signal twisted with GND) or shielded wires are used to make the audio interface connections between the DSP and WM8766-EV1B platforms. This is to ensure that no interference or noise is picked up by the clocks or data lines, thus reducing performance and reliability. When the WM8766 is set in Slave Mode, the jumpers on header H1 should be removed, disconnecting the digital input section of the evaluation board. The audio interface timing and data signals from the DSP platform should then be connected as shown in Figure 19. The signals should be connected to H1 and not on the header strips J16 and J25 running up each side of the device. Connecting the signals on the output side of the level-shift IC (U7) will cause drive contention between U7 and the DSP and could result in damage to either or both devices. In most cases, the DSP supplies will be set around 3V for low power portable applications. The inputs to the level-shift IC (74ALVC164245) have a TTL threshold (i.e. Logic High = +2V(min); Logic Low = +0.8V(max)) and low input current requirements (i.e. 15uA max) allowing most DSP's to connect directly. DACDAT GND DACLRC GND DACBCLK GND DACMCLK_IN GND H1 Figure 19 Connections from DSP Platform The digital inputs to the WM8766 have a CMOS threshold (i.e. Logic High (min) = DBVDDx0.7; Logic Low (max) = DBVDDx0.3). These are met directly by the level shift IC outputs. When the WM8766 is set to Master mode, the jumpers on header H1 should be removed, disconnecting the digital input section of the evaluation board. If an external MCLK signal is being used (i.e. supplied by the DSP) then the DSP platform should be connected as shown in Figure 20. The signals should be connected to H1 and not on the header strip J16 running up the side of the device. Connecting the signals on the output side of the level-shift IC (U7) will cause drive contention between U7 and the DSP and could result in damage to either or both devices. In most cases, the DSP supplies will be set around +3V for low power portable applications. The inputs to the level-shift IC (74ALVC164245) have a TTL threshold (i.e. Logic High = +2V(min); Logic Low = +0.8V(max)) and low input current requirements (i.e. 15uA max) allowing most DSPs to connect directly. The BCLK and LRCLK signals that will be provided by the WM8766 in Master mode should be connected directly from the relevant pins on header strip J16. These are CMOS threshold voltages and should be compatible with most DSP platforms. w Rev 1.2 November 2003 23 WM8766-EV1M DACDAT GND DACMCLK_IN GND H1 Figure 20 Timing Connections from DSP Platform The digital inputs to the WM8766 have a CMOS threshold (i.e. Logic High (min) = DBVDDx0.7; Logic Low (max) = DBVDDx0.3). These are met directly by the level shift IC outputs. w Rev 1.2 November 2003 24 WM8766-EV1M EVALUATION SUPPORT The aim of this evaluation kit is to help you to become familiar with the functionality and performance of the WM8766, 6-channel CODEC. If you require more information or require technical support please contact Wolfson Microelectronics Applications group through the following channels: Email: [email protected] Telephone Apps: (+44) 131 272 7070 Fax: (+44) 131 272 7001 Mail: Applications Department at address on last page. or contact your local Wolfson representative. Additional information may be made available from time to time on our web site at http://www.wolfsonmicro.com w Rev 1.2 November 2003 25 WM8766-EV1M IMPORTANT NOTICE Wolfson Microelectronics plc (WM) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current. All products are sold subject to the WM terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. WM warrants performance of its products to the specifications applicable at the time of sale in accordance with WM’s standard warranty. Testing and other quality control techniques are utilised to the extent WM deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed, except those mandated by government requirements. In order to minimise risks associated with customer applications, adequate design and operating safeguards must be used by the customer to minimise inherent or procedural hazards. Wolfson products are not authorised for use as critical components in life support devices or systems without the express written approval of an officer of the company. Life support devices or systems are devices or systems that are intended for surgical implant into the body, or support or sustain life, and whose failure to perform when properly used in accordance with instructions for use provided, can be reasonably expected to result in a significant injury to the user. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. WM assumes no liability for applications assistance or customer product design. WM does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right of WM covering or relating to any combination, machine, or process in which such products or services might be or are used. WM’s publication of information regarding any third party’s products or services does not constitute WM’s approval, license, warranty or endorsement thereof. Reproduction of information from the WM web site or datasheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations and notices. Representation or reproduction of this information with alteration voids all warranties provided for an associated WM product or service, is an unfair and deceptive business practice, and WM is not responsible nor liable for any such use. Resale of WM’s products or services with statements different from or beyond the parameters stated by WM for that product or service voids all express and any implied warranties for the associated WM product or service, is an unfair and deceptive business practice, and WM is not responsible nor liable for any such use. ADDRESS: Wolfson Microelectronics plc 20 Bernard Terrace Edinburgh EH8 9NX United Kingdom Tel :: +44 (0)131 272 7000 Fax :: +44 (0)131 272 7001 Email :: [email protected] w Rev 1.2 November 2003 26