User's Guide SBAU198 – April 2012 ADS8028EVM-PDK Figure 1. ADS8028EVM-PDK This user's guide describes the characteristics, operation, and use of the ADS8028EVM-PDK. This evaluation module and performance development kit (EVM-PDK) is an evaluation system for the ADS8028, a 12-bit, 1-MSPS, 8-channel, successive approximation register (SAR) analog-to-digital converter (ADC). The EVM-PDK allows evaluation of all aspects of the ADS8028 device.
www.ti.com 1 2 3 4 5 Contents EVM Overview ............................................................................................................... 3 EVM Setup ................................................................................................................... 4 ADS8028EVM Hardware Details .......................................................................................... 6 Using the ADS8028EVM-PDK with ADCPro ...................................................................
EVM Overview www.ti.com 1 EVM Overview The ADS8028EVM-PDK is designed to evaluate the ADS8028. The ADS8028 is a 12-bit, 8-channel, multiplexed, SAR ADC, with a maximum throughput rate of 1 MSPS. The ADS8028 also offers an internal 2.5-V voltage reference and internal temperature sensor with 0.25°C resolution. The ADS8028EVM allows access to every pin of the converter and makes it easy to connect the ADS8028 SPI™-compatible serial interface to any host microprocessor or TI DSP based system with 1.8-V, 3.
EVM Setup 2 www.ti.com EVM Setup This section is a quick guide to begin evaluating the ADS8028EVM with ADCPro. 2.1 Default Jumper Configuration Figure 2 shows the location of jumpers on the EVM and their respective factory default settings. Figure 2. Jumper Locations and Default Settings Table 3 lists the jumpers on the ADS8028EVM and their factory default settings. Table 3. Default Jumper Configurations Jumper Default Position J-1 Open Description 1.8-V logic not selected J-3 Short 3.
EVM Setup www.ti.com 2.2 ADS8028EVM-PDK Kit Operation To prepare to evaluate the ADS8028 with the ADS8028EVM-PDK, complete the following steps: 1. Verify the ADS8028EVM jumper settings from the factory as shown in Figure 2 and also listed in Table 3. 2. Install ADCPro and the ADS8028EVM plug-in software. Complete hardware connections and driver installation as per the ADCPro HW/SW Installation Manual. Use the following jumper settings on the MMB0 to configure power with the ac adapter.
ADS8028EVM Hardware Details 3 www.ti.com ADS8028EVM Hardware Details Figure 3 shows the location of headers J-ANALOG, J-DIGITAL, and J-POWER and their assigned pin numbers. The notation J-NAME.<#> is used in this user's guide for identifying header pins. For example, J-ANALOG.1 refers to pin 1 on the J-ANALOG header. J-ANALOG.1 J-DIGITAL.1 2 Pin 1 2 3 4 3 4 5 6 5 6 7 8 7 8 9 10 9 10 11 12 11 12 13 14 13 14 15 16 15 16 17 18 17 18 19 20 19 20 J-POWER.
ADS8028EVM Hardware Details www.ti.com 3.1 Analog Inputs The ADS8028 provides eight single-ended input channels plus an internal temperature sensor. The eight analog input channels to the ADS8028 (AIN0 to AIN7) are connected to J-ANALOG on the ADS8028EVM. Channels 0 and 1 are buffered converter inputs. The OPA836 is configured as a unity-gain buffer on these channels. Channels 2 to 7 connect directly to the converter with an option to add an RC filter before the converter input.
ADS8028EVM Hardware Details 3.2 www.ti.com Digital Control The SPI digital control signals are applied directly to the J-DIGITAL header on the ADS8028EVM. When using the ADS8028EVM-PDK (the combination of the ADS8028EVM, MMB0 motherboard, and ADCPro software), these signals are supplied by the MMB0 motherboard through J4.
ADS8028EVM Hardware Details www.ti.com 3.3 Power Supply The ADS8028EVM requires two power-supply rails: one 5-V analog supply (AVDD) and a configurable digital interface (BVDD). Three selectable voltages are available for the digital interface to make the EVM compatible with different logic levels. Jumpers J-1, J-3, and J-5 on the ADS8028EVM select 1.8-V, 3.3-V, or 5-V BVDD digital interface voltages, respectively. Refer to Table 3 for the ADS8028EVM jumper functions and default settings.
ADS8028EVM Hardware Details 3.4 www.ti.com Voltage Reference The ADS8028EVM allows the user flexibility to select different voltage reference sources for the ADS8028. Options include the: • ADS8028 internal 2.5-V voltage reference, • Onboard REF5025 2.5-V reference, or • External reference source When the ADS8028 powers up, the internal 2.5-V reference is selected as the reference source by default.
Using the ADS8028EVM-PDK with ADCPro www.ti.com 4 Using the ADS8028EVM-PDK with ADCPro This section covers the use of the ADS8028EVM-PDK plug-in for ADCPro. For general ADCPro software use and instructions, refer to the ADCPro User's Guide. The ADS8028EVM-PDK plug-in for ADCPro provides complete control over all ADS8028 settings. It consists of a tabbed interface (see Figure 8), with different functions available on each tab.
Using the ADS8028EVM-PDK with ADCPro 4.2 www.ti.com Channel Selection Tab The ADS8028 can acquire data from one to eight channels, sequentially. The Channel Select tab provides the control to select which channels are sampled. A channel is selected to be sampled if a check mark is seen in the box corresponding to the channel number. Channels are listed sequentially, starting with channel 0 (AIN0) at the top of the list and channel 7 (AIN7) at the bottom.
Schematics and Bill of Materials www.ti.com The Reference Source control selects between the ADS8028 internal voltage reference (INT) and an external voltage reference source (EXT). Selecting EXT disables the internal voltage reference and allows the user to specify the applied reference voltage in the Reference Voltage indicator to display the correct voltage output values. The Temperature Averaging control configures the ADS8028 to average eight temperature measurements.
Schematics and Bill of Materials www.ti.com Table 5. ADS8028EVM Bill of Materials 14 Item No. Qty Value 1 1 — 2 2 430 pF 3 5 1 µF 4 3 10 µF 5 0 — 6 2 7 Ref Des Description Manufacturer Part Number Printed Circuit Board, 3.2 In x 1.7 In x 0.
4 3 2 1 EXT_REF Bipolar Input -2V -> +2V TRIM 5 C13 1u 1u A VOUT 6 3 TEMP NC 7 2 VIN 4 GND DNC 8 U4 REF5025AID 1 DNC C12 AVDD Ground unused channels with jumper to avoiding floating inputs 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 J-ANALOG Analog Connector Signal Pin # AGND 1 A0+ 2 AGND 3 A1+ 4 AGND 5 A2+ 6 AGND 7 A3+ 8 AGND 9 A4+ 10 AGND 11 A5+ 12 AGND 13 A6+ 14 VCOM 15 A7+ 16 AGND 17 REF18 AGND 19 REF+ 20 J-SMA SMA Input Single-Ended Input 0.1V* -> +2.
Evaluation Board/Kit Important Notice Texas Instruments (TI) provides the enclosed product(s) under the following conditions: This evaluation board/kit is intended for use for ENGINEERING DEVELOPMENT, DEMONSTRATION, OR EVALUATION PURPOSES ONLY and is not considered by TI to be a finished end-product fit for general consumer use. Persons handling the product(s) must have electronics training and observe good engineering practice standards.
EVALUATION BOARD/KIT/MODULE (EVM) ADDITIONAL TERMS Texas Instruments (TI) provides the enclosed Evaluation Board/Kit/Module (EVM) under the following conditions: The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user indemnifies TI from all claims arising from the handling or use of the goods.
FCC Interference Statement for Class B EVM devices This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
【Important Notice for Users of this Product in Japan】 】 This development kit is NOT certified as Confirming to Technical Regulations of Radio Law of Japan If you use this product in Japan, you are required by Radio Law of Japan to follow the instructions below with respect to this product: 1. 2. 3. Use this product in a shielded room or any other test facility as defined in the notification #173 issued by Ministry of Internal Affairs and Communications on March 28, 2006, based on Sub-section 1.
EVALUATION BOARD/KIT/MODULE (EVM) WARNINGS, RESTRICTIONS AND DISCLAIMERS For Feasibility Evaluation Only, in Laboratory/Development Environments. Unless otherwise indicated, this EVM is not a finished electrical equipment and not intended for consumer use.
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