Texas Instruments ADS8668, User Manual

Page 1: ...ted by the ADS86xxEVM Table 1 Devices Supported By the ADS86xxEVM Device Description ADS8698 8 channel integrated 18 bit SAR ADC with ALARM ADS8688A 8 channel integrated 16 bit SAR ADC with ALARM ADS8678 8 channel integrated 14 bit SAR ADC with ALARM ADS8668 8 channel integrated 12 bit SAR ADC with ALARM Windows is a registered trademark of Microsoft Corporation SPI is a trademark of Motorola Mobi...

Page 2: ...nnels AIN0 AIN1 AIN2 and AIN3 6 2 ADS86xxEVM Analog Input Connections for Channels AIN4 AIN5 AIN6 and AIN7 6 3 Power Supply Connections Diagram 11 4 ADS86xxEVM Default Jumper Settings 12 5 Bottom View of the Simple Capture Card with the microSD Memory Card Installed 14 6 Bottom View of the ADS86xxEVM Board with the microSD Memory Card Installed 14 7 Connecting the ADS86xxEVM Board to the Simple Ca...

Page 3: ...6xxEVM 1 2 Related Documentation 4 3 J7 Analog Interface Connections 7 4 Connecting Negative Analog Inputs to Ground 7 5 Using Onboard Second Order Butterworth Low Pass Filters 8 6 Bypassing the Onboard Second Order Butterworth Low Pass Filters 8 7 Selecting the Reference for the ADS86xxEVM 8 8 External Reference Connections 8 9 Connector J19 Pin Out 9 10 Jumper Settings for Generating HVDD and HV...

Page 4: ...56 V and 0 V to 1 28 V The input range selection is done by software programming the device internal registers This selection is independent for each channel The device offers a 1 MΩ constant resistive input impedance irrespective of the selected input range This user guide includes circuit description a schematic diagram and a bill of materials for the ADS86xxEVM circuit board Table 2 Related Doc...

Page 5: ...upport circuitry as a design example to match ADC performance 3 3 V slave SPI Serial interface header for easy connection to the simple capture card Designed for a 5 V analog supply Integrated 4 096 V voltage reference Bipolar 10 24 V 5 12 V 2 56 V 1 28 V and 0 64 V or unipolar 0 V to 10 24 V 0 V to 5 12 V 0 V to 2 56 V and 0 V to 1 28 V input ranges for each channel Onboard second order Butterwor...

Page 6: ...nput connections for channels AIN0 to AIN3 and channels AIN4 to AIN7 respectively Table 3 lists the analog interface connections for J7 Figure 1 ADS86xxEVM Analog Input Connections for Channels AIN0 AIN1 AIN2 and AIN3 Figure 2 ADS86xxEVM Analog Input Connections for Channels AIN4 AIN5 AIN6 and AIN7 6 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedbac...

Page 7: ...e analog input for channel AIN2 J7 13 A3 Negative analog input for channel AIN3 J7 15 A4 Negative analog input for channel AIN4 J7 17 A5 Negative analog input for channel AIN5 J7 19 GND Analog ground connection 3 1 Connecting Negative Inputs to Ground The negative analog inputs for all channels except for the AUX channel are capable of accepting a 100 mV signal The negative analog inputs can eithe...

Page 8: ...een pins 2 and 3 Table 6 Bypassing the Onboard Second Order Butterworth Low Pass Filters Channel Jumper Position Jumper Position AIN0 J25 Open J8 Closed between pins 2 and 3 AIN1 J31 Open J10 Closed between pins 2 and 3 AIN2 J30 Open J11 Closed between pins 1 and 2 AIN3 J15 Open J9 Closed between pins 1 and 2 3 3 Selecting the Reference Mode for the ADS86xxEVM The ADS86xxEVM can either operate on ...

Page 9: ...ut for the ADC J19 38 SDI Data input for the ADC J19 39 SDO Data output from the ADC Digital connections for the onboard micro secure digital J19 45 49 EVMSDxxxxx microSD card J19 2 J19 10 J19 16 J19 50 GND Ground connections 4 1 Serial Interface SPI The ADS86xx device uses SPI serial communication in mode 1 CPOL 0 CPHA 1 with clock speeds up to 18 MHz The ADS86xxEVM offers 49 9 Ω resistors betwee...

Page 10: ...ition for Using an Onboard Switching Regulator J12 Closed between pins 1 and 2 J14 Closed between pins 1 and 2 J17 Open HVDD and HVSS for buffers U4 and U5 can also be generated by providing external high voltage supplies on J18 as shown in Table 11 Table 12 and Figure 3 illustrate the power supply connections for external supplies Table 11 Jumper Settings for Generating HVDD and HVSS from Externa...

Page 11: ... card or by converting an external 5 V supply to a regulated 5 V supply by using the REG71055 charge pump and the TPS7A4901 linear regulator The DVDD digital supply for the ADC is derived from a 3 3 V supply from the simple capture card 11 SBAU245A June 2015 Revised July 2015 ADS86xxEVM PDK Evaluation Module Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 12: ...kit prior to operation 6 1 Default Jumper Settings Figure 4 details the default jumper settings Table 13 provides the configuration for these jumpers Figure 4 ADS86xxEVM Default Jumper Settings 12 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 13: ... the microSD memory card included in the kit is installed in the microSD socket P6 on the back of the simple capture card before connecting the EVM to the computer Otherwise as a result of improper boot up Windows cannot recognize the ADS86xxEVM PDK as a connected device Complete the following steps to install the software 1 Verify the microSD memory cards are installed on the simple capture card ...

Page 14: ... the factory with the necessary firmware files for the simple capture card to boot properly In addition to the simple capture card firmware files application and MLO files the microSD memory cards contain the ADS86xxEVM PDK software installation files 6 2 2 Verify Jumpers are in the Factory Default Position and Connect the Hardware The ADS86xxEVM PDK includes both the ADS86xxEVM and the simple cap...

Page 15: ...ser must have administrator privileges to install the EVM software The following steps list the directions to install the software 1 Open the Windows explorer and locate the microSD memory card labeled ADS86xxEVM in the browser as a removable storage device 2 Navigate to the ADS86xxEVMGUI Version x x Volume folder 3 Run the installer by double clicking the setup exe file This action installs the E...

Page 16: ...tory Screen Figure 10 License Agreement Screen 6 Select the I Accept the License Agreement radial button and click Next 16 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 17: ...llation Screen 8 A progress bar appears as shown in Figure 12 this step takes a few minutes Figure 12 Progress Bar Screen 9 The progress bar is followed by an installation complete notice 17 SBAU245A June 2015 Revised July 2015 ADS86xxEVM PDK Evaluation Module Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 18: ...mpts do not appear if the simple capture card device driver is already installed on your system Following are the steps required to install the simple capture card device driver 1 Immediately after the ADS86xxEVM software installation is complete prompts appear to install the simple capture card device driver see Figure 14 and Figure 15 2 A computer restart may be required to finish the software i...

Page 19: ...ou change a setting on the ADS86xxEVM GUI the setting immediately updates on the board Settings on the ADS86xxEVM correspond to settings described in the ADS86xx product data sheet available for download at www ti com see the product data sheet for details To load the ADS86xxEVM GUI follow these steps Step 1 Make sure the PDK kit is configured and powered up as explained in Section 6 2 2 Step 2 St...

Page 20: ...INx_PD box if a channel is powered down that channel turns grey in system block view The voltage range for each channel can be selected from a drop down menu corresponding to each channel in the system block diagram view as shown in Figure 17 The window for selecting the input voltage range is displayed in Figure 18 Figure 17 System Block Diagram View Figure 18 Selecting the Input Range for the Ch...

Page 21: ...register For reading a register the user must select the register in the register map and click the Read Register button All registers can be read by clicking the Read All button The values for all registers can be saved in a configuration file cfg by the Save Config button The saved configuration can be loaded back by using the Load Config button Changes made in the register map view are reflecte...

Page 22: ... can be activated by clicking on the Manual Channel N button on the left side of the GUI window and by selecting Data Capture from the drop down menu see Figure 21 In manual mode data are captured for the channel selected by the Channel Name drop down menu The sampling rate and number of samples for the data capture can be entered in the ADC Capture Settings box The ADS86xxEVM GUI supports a sampl...

Page 23: ...n of Equation 1 The number of samples to be captured per channel must be entered in the ADC Capture Settings box The number of samples per channel value is adjusted to the closest power of 2 by the GUI The GUI supports a maximum capture of 8 388 608 samples per capture The maximum number of samples per channel that can be captured in auto mode is determined by Equation 3 Number of Samples per Chan...

Page 24: ...ta Capture in Auto Mode with Single Graph View Figure 23 Data Capture in Auto Mode with Multi Graph View 24 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 25: ...g the Log Data To File button as shown in Figure 24 A window appears for selecting the location and entering the name of the file for saving the captured data Figure 24 Saving the Captured Data 25 SBAU245A June 2015 Revised July 2015 ADS86xxEVM PDK Evaluation Module Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 26: ...a set and displays that data The input channel AINx for the histogram analysis can be selected from the channel drop down menu and the data capture settings can be entered in boxes on the left side of the graph Figure 25 shows the histogram analysis page Figure 25 Histogram Analysis The following parameters are calculated using the histogram analysis Code Spread Is the number of different codes ca...

Page 27: ...rmance analysis display The input channel AINx for FFT analysis can be selected from the channel drop down menu and the data capture settings can be entered in boxes on the left side of the graph The FFT calculated parameters are shown on the bottom side of the graph Figure 26 FFT Analysis Input signal frequency for FFT analysis The GUI analyses the FFT to provide signal power dBFs SNR SINAD THD S...

Page 28: ...tton when in manual or auto mode Individual channel threshold levels and hysteresis levels can be programmed in the Configure Alarm Settings pop up window The ALARM feature can be enabled or disabled by checking or unchecking the Alarm Enable check box Click the Config Alarm Settings button to program device registers with correct data as shown in Figure 27 The user can also program these values b...

Page 29: ... phase of signals captured in auto mode When the signals on different channels are sampled in auto mode a deterministic phase difference between signals is introduced resulting from the time difference between sampling instants The phase difference is dependent on sampling rate input signal frequency number of channels and initial phase difference The phase compensation analysis page compensates f...

Page 30: ...DK Kit Operation www ti com Figure 28 Phase Compensation Analysis 30 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 31: ...he GUI window In simulation mode the GUI does not connect to the ADS86xxEVM board and only displays the results for one set of captured data stored in the computer Figure 29 shows the ADS86xxEVM GUI running in simulation mode Figure 29 Simulation Mode 31 SBAU245A June 2015 Revised July 2015 ADS86xxEVM PDK Evaluation Module Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated...

Page 32: ...VX 06035C104KAT2A 6 4 C17 C22 C27 C28 CAP CERM 2200pF 50V 5 C0G NP0 0603 TDK C1608C0G1H222J 7 4 C23 C25 C29 C31 CAP CERM 1000pF 50V 5 C0G NP0 0402 MuRata GRM1555C1H102JA01D 8 4 C32 C35 C49 C50 CAP CERM 22uF 25V 10 X7R 1210 MuRata GRM32ER71E226KE15L 9 3 C34 C36 C53 CAP CERM 10uF 25V 10 X7R 1206 MuRata GRM31CR71E106KA12L 10 2 C37 C54 CAP CERM 10uF 35V 10 X7R 1206 Taiyo Yuden GMK316AB7106KL C4 C12 C1...

Page 33: ...W 0402 Vishay Dale CRCW040210K0FKED 41 5 R11 R21 R22 R74 R76 RES 10 0Meg ohm 1 0 063W 0402 Vishay Dale CRCW040210M0FKED 42 1 R12 RES 1 0k ohm 5 0 125W 0805 Vishay Dale CRCW08051K00JNEA 43 3 R13 R15 R18 RES 47 0k ohm 1 0 1W 0603 Yageo America RC0603FR 0747KL 44 1 R17 RES 220k ohm 5 0 063W 0402 Vishay Dale CRCW0402220KJNED 45 1 R19 RES 100 ohm 1 0 1W 0603 Vishay Dale CRCW0603100RFKEA 46 17 R2 R3 R5 ...

Page 34: ... 5000 69 9 TP2 TP10 Test Point Miniature White TH Keystone 5002 70 2 U1 U3 Op Amp Precision 5 5MHz Low Noise RRIO with e trim Texas Instruments OPA376AIDBVR IC 3V to 36V 200mA Ultralow Noise High PSRR LDO Negative 71 1 U10 Texas Instruments TPS7A3001DGN Linear Regulator 72 1 U11 IC 2K Serial EEPROM Atmel AT24C02B 73 1 U2 16 bit 500KSPS 8 Channel SAR ADC Texas Instruments ADS8688IDBT 74 2 U4 U5 OpA...

Page 35: ... NOTE Board layouts are not to scale These figures are intended to show how the board is laid out these figures are not intended to be used for manufacturing ADS86xxEVM PCBs Figure 30 ADS86xxEVM PCB Top Layer L1 35 SBAU245A June 2015 Revised July 2015 ADS86xxEVM PDK Evaluation Module Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 36: ... ti com Figure 31 ADS86xxEVM PCB Ground Layer L2 Figure 32 ADS86xxEVM PCB Analog Power Layer L3 36 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 37: ...ematics Figure 33 ADS86xxEVM PCB Digital Power Layer L4 Figure 34 ADS86xxEVM PCB Ground Layer L5 37 SBAU245A June 2015 Revised July 2015 ADS86xxEVM PDK Evaluation Module Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 38: ...ayout and Schematics www ti com Figure 35 ADS86xxEVM PCB Bottom Layer L6 38 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 39: ...atics Figure 36 and Figure 37 illustrate schematics for the ADS86xxEVM PDK Figure 36 ADS86xx Interface Schematic 39 SBAU245A June 2015 Revised July 2015 ADS86xxEVM PDK Evaluation Module Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 40: ...out and Schematics www ti com Figure 37 Power and SDCC Interface Schematic 40 ADS86xxEVM PDK Evaluation Module SBAU245A June 2015 Revised July 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 41: ...nts section 4 Added reference to Section 8 3 in overview of Section 8 32 Added Schematics section 39 NOTE Page numbers for previous revisions may differ from page numbers in the current version 41 SBAU245A June 2015 Revised July 2015 Revision History Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 42: ...ring the warranty period to the address designated by TI and that are determined by TI not to conform to such warranty If TI elects to repair or replace such EVM TI shall have a reasonable time to repair such EVM or provide replacements Repaired EVMs shall be warranted for the remainder of the original warranty period Replaced EVMs shall be warranted for a new full ninety 90 day warranty period 3 ...

Page 43: ... by Industry Canada to operate with the antenna types listed in the user guide with the maximum permissible gain and required antenna impedance for each antenna type indicated Antenna types not included in this list having a gain greater than the maximum gain indicated for that type are strictly prohibited for use with this device Concernant les EVMs avec antennes détachables Conformément à la rég...

Page 44: ... connecting any load to the EVM output If there is uncertainty as to the load specification please contact a TI field representative During normal operation even with the inputs and outputs kept within the specified allowable ranges some circuit components may have elevated case temperatures These components include but are not limited to linear regulators switching transistors pass transistors cu...

Page 45: ...F REMOVAL OR REINSTALLATION ANCILLARY COSTS TO THE PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES RETESTING OUTSIDE COMPUTER TIME LABOR COSTS LOSS OF GOODWILL LOSS OF PROFITS LOSS OF SAVINGS LOSS OF USE LOSS OF DATA OR BUSINESS INTERRUPTION NO CLAIM SUIT OR ACTION SHALL BE BROUGHT AGAINST TI MORE THAN ONE YEAR AFTER THE RELATED CAUSE OF ACTION HAS OCCURRED 8 2 Specific Limitations IN NO EVENT SHALL T...

Page 46: ...esponsible for compliance with all legal regulatory and safety related requirements concerning its products and any use of TI components in its applications notwithstanding any applications related information or support that may be provided by TI Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failur...

Page 47: ...Mouser Electronics Authorized Distributor Click to View Pricing Inventory Delivery Lifecycle Information Texas Instruments ADS8698EVM PDK ADS8688AEVM PDK ADS8678EVM PDK ADS8668EVM PDK ...