User's Guide SBAU126C – May 2007 – Revised May 2011 ADS1158EVM, ADS1258EVM, ADS1158EVM-PDK, and ADS1258EVM-PDK Figure 1. ADS1258EVM (Left) and ADS1258EVM-PDK (Right) This user's guide describes the characteristics, operation, and use of the ADS1158EVM and ADS1258EVM, both separately and as part of the ADS1158EVM-PDK or ADS1258EVM-PDK.
www.ti.com 1 2 3 4 5 6 7 8 9 10 Contents EVM Overview ............................................................................................................... 3 Analog Interface ............................................................................................................. 4 Digital Interface .............................................................................................................. 5 Power Supplies ...................................................................
EVM Overview www.ti.com 7 Reference Selection ........................................................................................................ 8 8 List of Switches ............................................................................................................ 10 9 ADS1258EVM Bill of Materials 1 EVM Overview 1.1 Features ..........................................................................................
Analog Interface 1.2 www.ti.com Introduction The ADS1258EVM is an evaluation module built to the TI Modular EVM System specification. It can be connected to any Modular EVM System interface card. The ADS1258EVM is available as a stand-alone printed circuit board (PCB) or as part of the ADS1258EVM-PDK, which includes an MMB0 motherboard. As a stand-alone PCB, the ADS1258EVM is useful for prototyping designs and firmware. Note that the ADS1258EVM has no microprocessor and cannot run software.
Digital Interface www.ti.com The AINCOM and multiplexer bypass pins are brought to J2, as shown in Table 3. AINCOM is connected to pin 12 on J2. An additional connection is made between J2.11 and J1.10; as a result of this connection, if J2.11 and J2.12 are shorted, and J1.9 and J1.10 are shorted, AINCOM is grounded; if only J2.11 and J2.12 are shorted, AINCOM is available on the EVM analog connector. The multiplexer bypass is available at J2.13–J2.14 (MUXOUP) and J2.15–J2.16 (MUXOUN).
Digital Interface www.ti.com Many pins on J6 have weak pull-up resistors. These resistors provide default settings for many of the control pins. Many pins on J6 correspond directly to ADS1258 pins, as shown in Table 4. See the ADS1258 data sheet for complete details on these pins. Table 4. J6—Serial Interface Pins PIN NUMBER PIN NAME SIGNAL NAME I/O TYPE PULL-UP J6.1 CNTL CNTL In None Optional ADS1258 START pin control; see text J6.2 GPIO0 PDWN In High ADS1258 power-down pin J6.
Power Supplies www.ti.com 4 Power Supplies J5 is the power-supply input connector, as shown in Table 5. Table 5. J5 Configuration—Power-Supply Input 4.1 PIN NUMBER PIN NAME FUNCTION REQUIRED? J5.1 +VA Not used No J5.2 –VA Not used No J5.3 +5VA +5V analog supply Always J5.4 –5VA –5V analog supply Only in bipolar mode J5.5 DGND Digital ground input Only if DGND is selected on J4 J5.6 AGND Analog ground input Only if AGND is selected on J4 J5.7 +1.8VD 1.
Voltage Reference 5 www.ti.com Voltage Reference The ADS1258EVM has a DAC-controlled voltage reference circuit. The DAC used is a TI DAC8571, controlled through the I2C. The address is set to 1001100. The output of the DAC is multiplied by two, giving a range of approximately 0V to 5V. The DAC circuit is designed for low drift, but is uncalibrated. For absolute accuracy, measure the DAC output and adjust as needed. The DAC high resolution reduces the need for mechanical trimming.
EVM Operation www.ti.com 7 EVM Operation The following sections provide information on the analog input, digital control, and general operating conditions of the ADS1258EVM. 7.1 Analog Input The analog input sources can be applied directly to J1 (top or bottom side) or through signal-conditioning modules available for the the modular EVM system. Signals can be applied directly to J2 for the additional available channels. 7.
EVM Operation 7.4 www.ti.com Default Jumper Settings and Switch Positions Figure 3 shows the jumpers found on the EVM and the factory default conditions for each one. Figure 3. ADS1258EVM Default Jumper Locations The jumpers on J4 provide a convenient way to measure the current for any of the power-supply currents: AVDD (analog +V power), DVDD (digital power), AVSS (analog –V power), or the ground connections VGND and DGND.
ADS1258EVM-PDK Kit Operation www.ti.com 8 ADS1258EVM-PDK Kit Operation This section provides information on using the ADS1258EVM-PDK, including setup, program installation, and program usage. To prepare Step 1. Step 2. Step 3. Step 4. Step 5. Step 6. Step 7. to evaluate the ADS1258 with the ADS1258EVM-PDK, complete the following steps: Install the ADCPro software (if not already installed). Install the ADS1258EVM-PDK EVM plug-in software. Set up the ADS1258EVM-PDK.
ADS1258EVM-PDK Kit Operation 8.2 www.ti.com Setting Up the ADS1258EVM-PDK The ADS1258EVM-PDK contains both the ADS1258EVM and the MMB0 motherboard; however, the devices are shipped unconnected. Follow these steps to set up the ADS1258EVM-PDK: Step 1. Unpack the ADS1258EVM-PDK kit. Step 2. Set the jumpers and switches on the MMB0 as shown in Figure 4: • Set the Boot Mode switch to USB. • Connect +5V and +5VA on jumper block J13 (if +5V is supplied from +5VA).
ADS1258EVM-PDK Kit Operation www.ti.com 3. Plug the ADS1258EVM into the MMB0, as shown in Figure 5. Figure 5. Connecting the ADS1258EVM to the MMB0 CAUTION Do not misalign the pins when plugging the ADS1258EVM into the MMB0. Check the pin alignment carefully before applying power to the PDK. Step 3. 8.3 Set the jumpers and switches on the ADS1258EVM as illustrated in Figure 3 (note that these settings are the factory-configured settings for the EVM): • Set jumper block J4 as illustrated in Figure 3.
ADS1258EVM-PDK Kit Operation 8.4 www.ti.com Connecting the Power Supply The ADS1258EVM-PDK can be operated with a unipolar +5V supply or a bipolar ±5V supply. If the ADS1258EVM-PDK is to be operated in unipolar mode only, either an ac adapter or a lab power supply can be used. If the ADS1258EVM-PDK is to be operated in bipolar mode, a ±5V power supply must be connected; an ac adapter cannot be used. When the MMB0 DSP is powered properly, LED D2 glows green. The green light indicates that the 3.
ADS1258EVM-PDK Kit Operation www.ti.com 8.4.2 Connecting a Laboratory Power Supply A laboratory power supply can be connected through terminal block J14 on the MMB0, as shown in Figure 7. Both unipolar and bipolar configurations are supported. To • • • use a unipolar lab power-supply configuration: Disconnect J12 on the MMB0. Connect a +5V dc supply to the +5VD terminal on J14. Connect ground of the dc supply to the GND terminal on J14.
ADS1258EVM-PDK Kit Operation 8.5 www.ti.com Running the Software and Completing Driver Installation NOTE: The software is continually under development. These instructions and screen images are current at the time of this writing, but may not exactly match future releases. The program for evaluating the ADS1258EVM-PDK is called ADCPro. This program uses plug-ins to communicate with the EVM. The ADS1258EVM-PDK plug-in is included in the ADS1258EVM-PDK package.
ADS1258EVM-PDK Kit Operation www.ti.com Figure 8.
ADS1258EVM-PDK Kit Operation www.ti.com Figure 9.
ADS1258EVM-PDK Kit Operation www.ti.com Figure 10.
ADS1258EVM-PDK Kit Operation www.ti.com Figure 11. NI-VISA Driver Complete Installation This should complete the installation of the NI-VISA drivers. You can verify proper installation by opening the Device Manager and locating the driver as shown in Figure 12. Figure 12.
ADS1258EVM-PDK Kit Operation www.ti.com 8.5.2 USBStyx Driver Installation 1. Start the software by selecting ADCPro from the Windows Start menu. The screen in Figure 13 appears. Figure 13.
ADS1258EVM-PDK Kit Operation www.ti.com 2. Select ADS1258EVM from the EVM drop-down menu. The ADS1258EVM-PDK plug-in appears in the left pane, as shown in Figure 14. Figure 14. ADS1258EVM-PDK Plug-In Display Window 3. The ADS1258EVM-PDK plug-in window has a status area at the top of the screen. When the plug-in is first loaded, the plug-in searches for the board. You will see a series of messages in the status area indicating this action. 4.
ADS1258EVM-PDK Kit Operation www.ti.com Figure 15. Install New Driver Wizard Screen 1 Figure 16.
ADS1258EVM-PDK Kit Operation www.ti.com Figure 17. Install New Driver Wizard Screen 3 Figure 18.
ADS1258EVM-PDK Kit Operation www.ti.com Figure 19. Install New Driver Wizard Screen 5 5. Once Windows finishes installing the software driver, the plug-in downloads the firmware to the MMB0. The status area will display Connected to EVM when the device is connected and ready to use. If the firmware does not load properly, you can try resetting the MMB0 by pressing reset and then reloading the plug-in. 6. You can verify the proper installation of the USBStyx driver using the Device Manager.
Evaluating with the ADCPro Software 9 www.ti.com Evaluating with the ADCPro Software The evaluation software is based on ADCPro, a program that operates using a variety of plug-ins. (The ADS1258EVM plug-in is installed as described in the installation section.) To use ADCPro, load an EVM plug-in and a test plug-in. To load an EVM plug-in, select it from the EVM menu. To load a test plug-in, select it from the Test menu. To unload a plug-in, select the Unload option from the corresponding menu.
Evaluating with the ADCPro Software www.ti.com 9.1.1 MUX Tab The ADS1258 multiplexer can work in two modes, selected by the controls Fixed Channel or Auto Scan. When set to Fixed Channel mode, the screen will appear as shown in Figure 21. Figure 21. Mux Settings for Fixed Channel Mode On the Fixed Channel tab, the AINP and AINN of the ADS1258 are connected to the pins selected by the radio buttons.
Evaluating with the ADCPro Software www.ti.com When set to Auto Scan mode, the screen appears as shown in Figure 22. In this mode, the ADS1258 scans through all of the channels selected by checking the box next to the channel name. Note that the AIN channels are single-ended channels, referred to AINCOM. See the ADS1258 data sheet for details on all of the channel configurations.
Evaluating with the ADCPro Software www.ti.com The ADS1258 switch time delay can be set on the Switch Time Delay tab shown in Figure 23. This setting has effect only when in Auto Scan mode. The delay time can be set on this screen, from no delay (0μs) to 384μs. Figure 23. Switch Delay Settings Through the use of the External Chopping mode, the ADS1258 can remove the offset which might be introduced by signal conditioning circuits. It makes two measurements, which means the sampling rate is half as fast.
Evaluating with the ADCPro Software www.ti.com This action can be enabled on the Chopping tab shown in Figure 25. Figure 25.
Evaluating with the ADCPro Software www.ti.com 9.1.2 Clocks Tab The ADS1258 requires a clock to operate. This clock may be selected on this tab, as shown in Figure 26, using the Clock Source controls. Figure 26. Clock Settings The ADS1258 can operate from a 32kHz crystal, and using an internal PLL, generate a 15.729MHz clock. If the Internal setting is selected, this frequency is displayed in the Clock Frequency control. When MMB0 is selected, a 4MHz to 20MHz clock is supplied to the ADS1258EVM.
Evaluating with the ADCPro Software 9.1.3 www.ti.com GPIO Tab The GPIO Tab (shown in Figure 27) allows control of the ADS1258 GPIO pins. Down the center of this screen, the I/O Mode switches set whether each GPIO pin is an input or an output. Figure 27. GPIO Controls When selected as outputs, the Output buttons set the state of the GPIO pins; when pressed and lit, the pin will be driven high; when unlit, the pin will be driven low.
Evaluating with the ADCPro Software www.ti.com 9.1.4 Power and Ref Tab On this tab (shown in Figure 28), the power-supply mode for the ADS1258 may be selected. As explained earlier, the bipolar mode requires both a +5V and a –5V power supply and the appropriate jumper selections on the MMB0, so bipolar mode cannot be selected here if you are using an ac adaptor. With the appropriate power connections, the Power supply can be set to either Unipolar or Bipolar.
Evaluating with the ADCPro Software 9.1.5 www.ti.com Collecting Data Once you have configured the ADS1258 for your test scenario, pressing ADCPro's Acquire button will start the collection of the number of data points specified in the Test plug-in Block Size control. The ADS1258EVM-PDK plug-in will disable all the front panel controls while acquiring, and display a progress bar as shown in Figure 29. Figure 29.
Schematics and Layout www.ti.com 10 Schematics and Layout Schematics for the ADS1258EVM are appended to this user's guide. The bill of materials is provided in Table 9. 10.1 Bill of Materials NOTE: All components should be RoHS-compliant. Some part numbers may be either leaded or RoHS. Verify that purchased components are RoHS-compliant. Table 9. ADS1258EVM Bill of Materials Item No.
Revision History www.ti.com Table 9. ADS1258EVM Bill of Materials (continued) Item No. Qty 29 1 J4 Header Strip, 14-pin Samtec TSW-107-07-L-D 30 1 J3 Header Strip, 12-pin Samtec TSW-106-07-L-D 31 1 N/A ADS1258EVM PWB Texas Instruments 6474410 32 2 D1, D2 Schottky Diode Fairchild BAT54 33 1 D3 5.1V, Zener Diode On Semiconductor MMBZ5231BLT1G Not Installed 1 D4 5.1V, Zener Diode On Semiconductor MMBZ5231BLT1G 34 2 Q1, Q3 MOSFET, P-Channel, 2.
1 2 3 4 5 6 REVISION HISTORY REV ENGINEERING CHANGE NUMBER APPROVED J3 1 3 5 7 9 11 D C12 4 SCL SDA 0.1U R3 R4 1K 0.1% 1K 0.1% +5V S1 +3.3V VDD VREF VSENSE VOUT 5 NKK_SS14MDP2 1 2 3 4 S2 4 1 R5 3 DAC8571IDGK C4 0.1U C3 0.1U 20 U3 OPA301AIDBV 2 U2 TP2 OBREF C17 220U NKK_SS14MDP2 C13 1U DVDD GPIO5 C25 DVDD 1 4.7pF TP1 4 C26 4.7pF EPS_C-001R C6 C21 0.1U CNTL_S FSX_S GPIO7 CS SCLK DIN DOUT DRDY START PDWN RST CLKSEL CLK XTAL1 XTAL2 X1 29 C19 0.1U 0.
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