Evaluation Board for the AD5676R WLCSP
This user guide details the operation of the EVAL-AD5676RARDZ for the AD5676R WLCSP 16-bit, octal, voltage output, digital-to-analog converter (DAC).
The EVAL-AD5676RARDZ allows users to quickly prototype AD5676R circuits and reduce design time. The AD5676R operates from a single 2.7 V to 5.5 V supply. The AD5676R incorporates an internal 2.5 V reference to give a full-scale output voltage of 2.5 V or 5 V. An ADR4525 is also provided on-board as a 2.5V reference source. A different external reference voltage can be applied via the EXT_REF SMB connector or test pin if needed.
The EVAL-AD5676RARDZ interfaces to the USB port of a PC via a system demonstration platform board (SDP-K1 ). The Analysis | Control | Evaluation (ACE) software is available for download from the EVAL-AD5676RARDZ product page to use with the evaluation board to allow the user to program the AD5676R. A peripheral module interface (PMOD) connection is also available to allow the connection of microcontrollers to the evaluation board without the SDP-K1 board. When a microcontroller is used through the PMOD connection, the SDP-K1 board must be disconnected, and the user is unable to operate the ACE software.
The EVAL-AD5676RARDZ is compatible with the EVAL-SDP-CK1Z (SDP-K1), which should be purchased separately. A typical connection between the EVAL-AD5676RARDZ and the SDP-B controller board is shown below. For full details, see the AD5676R data sheet, which must be used in conjunction with this user guide when using the EVAL-AD5676RARDZ.
The EVAL-AD5676RARDZ uses the ACE evaluation software, which allows the evaluation and control of multiple evaluation systems.
The ACE installer installs the necessary SDP-K1 drivers and the Microsoft® .NET Framework 4 by default. The ACE software must be installed before connecting the SDP-K1 board to the USB port of the PC to ensure that the SDP-K1 board is recognized properly. For full instructions on how to install and use this software, see the ACE software page on the Analog Devices website.
After the installation is finished, the EVAL-AD5676RARDZ plug-in appears when the ACE software is opened.
To set up the evaluation board, take the following steps:
EVAL-AD5676RARDZ and SDP-K1 Board Connection
EVAL-AD5676RARDZ Plugin - Board View
EVAL-AD5676RARDZ Plugin - Chip View
The EVAL-AD5676RARDZ software is organized to appear similar to the functional block diagram shown in the AD5676R datasheet, which simplifies correlating the functions on the EVAL-AD5676RARDZ with the description in the AD5676R datasheet.
For a full description of each block, register, and its settings, see the AD5676R datasheet.
Some of the blocks and their functions are described in this section as they pertain to the evaluation board. The full-screen block diagram UI is shown below.
Block Diagram Functions
Label | Button/Function | Function/Description |
---|---|---|
A | General Commands | These consist of general command buttons with functions as follows. Apply Changes - Applies user inputs in the text fields, such as Label D, to the device. Read All - Reads the AD5676R's registers. Applicable only to select registers. Reset Chip - Initiates the software reset sequence for AD5676R. Diff - Shows the registers that are different on the device. Software Defaults - Returns all fields to the default settings. Memory Map side-by-side - Launches the Memory Map window side-by-side in the same window with the block diagram UI. |
B | Configuration WIndow | Used to set the configuration for the board. Select the gain setting from the Output Gain drop-down menu. A gain of 1 is the default. After setting up the initial configuration, click Apply to apply the values. These settings can be modified at any stage while evaluating the board. |
C | Select a Command | Contains command drop-down menus as described below. Command option drop-down menu selects how the user input data in Label D is transferred to the device. The user input data can be (Option 1) written to the input registers only or (Option 2) written to the input register and the DAC register (Label E). Channel group drop-down menu selects which channels are displayed in the Input Register block (Label D). (Option1) displays DAC Channel 0 to 3 while (Option 2) displays DAC Channel 4 to 7. |
D | Input Register | 16-bit data word to be transferred to the device. Data word should be in hexadecimal format. Select the channel group (Label C) to write to from the drop-down menu. Click Apply Changes (Label A) to transfer this 16-bit data word to the device. |
E | DAC Register | Displays the value that is currently present in the DAC register on the device. Update the DAC registers by selecting the appropriate command option or by toggling Load DAC (Label G) for specific channels or Software LDAC (Label J) for all channels. |
F | Software RESET | Returns the evaluation board and software to default values. |
G | Load DAC | Users can individually control which channel loads the values from the input registers field (Label D) to the DAC register. Click this button to initiate the software LDAC function and transfer the contents of the channel input register to the channel DAC register. |
H | DAC Config | DAC configuration options provide access to individual channel configuration, mainly, the power-down option, which can be set to either of the 3 states: Normal, 1kΩ to GND, or Tri-state. See datasheet for more info. |
I | Internal Reference | Configuration to Enable/Disable the on-chip reference. Note that the on-chip reference is enabled by default. Make sure to disable the on-chip reference when using an external reference source. |
J | Software LDAC (All Channels) | Loads the data word entered in the Input Registers field (Label D) to the device's DAC Register. Unlike the Load DAC (Label G), this command applies to all 8 channels of the AD5676R. |
K | Memory Map | Launches the Memory Map window in a separate tab as the Block Diagram window. See Memory Map for more details. |
All registers are fully accessible from the AD5676R Memory Map tab as shown below. This tab allows registers to be edited at the bit level. The bits shaded in dark gray are read-only bits and cannot be accessed from the ACE software. All other bits can be toggled.
All changes made in the memory map tab correspond to the block diagram. For example, if the internal register bit is enabled, it displays as enabled on the block diagram. Any bits or registers that are shown in bold in the memory map tab are modified values that have not been transferred to the evaluation board. Click Apply Changes to transfer the data to the evaluation board.
The EVAL-AD5676RARDZ provides an onboard 3.3 V regulator powered through the USB supply for the AD5676R main supply. If a different supply is required or if the evaluation board is controlled through the PMOD connector, an external supply must be provided by the external supply voltage (P8) connector. See the below table for more details.
An onboard 2.5V reference (ADR4525) is also provided. Every supply is decoupled to the ground with 10 µF tantalum and 0.1 µF ceramic capacitors.
PowerSupply Connectors
Connector Label | External Voltage Supplies Description |
---|---|
P8, Pin 1 | External analog power supply from 2.7 V to 5.5 V. |
P8, Pin 2 | Analog ground. |
EXT_REF | External voltage reference. |
Several link options are incorporated on the EVAL-AD5676RARDZ and must be set for the required operating conditions before using the board. The functions of these link options are described in the table below.
Link Functions
Link Name | Description |
---|---|
VDD_SEL, P10 | This link selects the analog voltage source for the AD5676R. There are three options, as follows: 5V0 - 5V supply from the SDP-K1 or the PMOD connectors. 3V3 - 3.3V supply from onboard LDO powered by the 5V0 supply. EXT - 2.7V to 5.5V supply from an external source connected to P8. |
REF_LDO_SEL | This link selects the analog voltage source for the onboard 2.5V reference ADM7160. There are three options, as follows: 5V0 - 5V supply from the SDP-K1 or the PMOD connectors. 3V3 - 3.3V supply from onboard LDO powered by the 5V0 supply. EXT - 2.7V to 5.5V supply from an external source connected to P8. |
REF, JP2 | This link selects the external voltage source for the AD5676R. There are two options, as follows: 2V5 - 2.5V supply from the onboard reference ADM7160. EXT - External supply coming from EXT_REF connector. |
P1 | This link connects the corresponding DAC output channel to the SMB connector. |
Ref | Connector Label | Function |
---|---|---|
A | P8 | External analog power supply from 2.7 V to 5.5 V. |
B | TP1 (GND) | Analog ground Testpoint. |
C | EXT_REF, J1 | External voltage reference input port. |
D | P2, P3, P5, P6 | Connector for SDP-K1 using standard Arduino form factor. |
E | SPI_PMOD | External SPI input using the PMOD standard pin configuration. |
F | I2C_PMOD | External I2C input using the PMOD standard pin configuration. |
G | P11 | DAC outputs from VOUT0 to VOUT7. |