\ CDB5461AU CDB5461AU Evaluation Board & Software Features General Description z Voltage The CDB5461AU is an inexpensive tool designed to evaluate the functionality and performance of the CS5461A. The evaluation board includes an LT1019 voltage reference, a C8051F320 microcontroller with a USB interface, and firmware.
CDB5461AU TABLE OF CONTENTS – TABLE OF CONTENTS ............................................................................................................. 2 – LIST OF FIGURES ..................................................................................................................... 3 – LIST OF TABLES ...................................................................................................................... 3 1. HARDWARE ................................................................
CDB5461AU 2.8.13 Time Domain Information .................................................................................. 25 2.9 EEPROM Window ........................................................................................................... 26 2.9.1 Read EEPROM ................................................................................................... 26 2.9.2 Write EEPROM ................................................................................................... 26 2.9.
CDB5461AU 1. HARDWARE 1.1 Introduction The CDB5461AU evaluation board provides a quick means of evaluating the CS5461A Power Meter IC. The CDB5461AU evaluation board operates from a single +5 V power supply. The evaluation board interfaces the CS5461A to a PC via an USB interface. To accomplish this, the board comes equipped with a C8051F320 microcontroller and a USB interface.
CDB5461AU 1.2.1 Analog Section The CDB5461AU evaluation board provides screw-type terminals (J23, J27) to connect input signals to the voltage and current channels. The screw terminals are labels as VIN+, VIN1, IIN+, and IIN-. A simple R-C network at each channel input provides a simple anti-alias filter. The evaluation board provides three voltage reference options for VREFIN to the CS5461A. The three voltage reference options include: VREFOUT from CS5461A, the on-board +2.
CDB5461AU INPUT Description VIN± or IIN± Selects External Signal J17 GND VREF VIN+ O O O O O J22 VIN+ VIN+ VIN+ VINVREF O GND O (Default) O O O J24 VINVINVIN- GND VREF IIN+ (Default) O O O O O J26 IIN+ IIN+ IIN+ IINVREF GND (Default) O O O O O IINIINIIN- (Default) O O O O O VIN+ VIN+ VIN+ VINVREF GND O O O O O VINVINVIN- GND VREF IIN+ O O O O O IIN+ IIN+ IIN+ IINVREF GND O O O O O IINIINIIN- Selects Grounding the Input GND VREF O VIN+ O O O O VIN+ VIN+ VIN+ VINVREF
CDB5461AU 1.2.3 Power Supply Section Table 4 illustrates the power supply connections to the evaluation board. The +5 binding post (J3) supplies the positive analog (VA+) for the CS5461A and the +2.5V reference. The VD+_EXT binding post (J5) supplies the digital section of the CS5461A (VD+) and level shifters. Jumper J8 allows the VD+ supply to be sourced from the VD+_EXT binding post (J5), the +5V binding post (J3), or the regulated 3.3V supply derived from the microcontroller.
CDB5461AU 1.3 Auto-boot Mode With a jumper connection on J18 (AUTO-BOOT ENABLE), the CS5461A operates in auto-boot mode and the CDB5461AU board operates in a stand-alone manner without connecting to a PC. When in auto-boot mode, a hardware reset (pressing on S1) will cause the CS5461A to boot up using the serial data from the serial EEPROM on the board (U10).
CDB5461AU 2. SOFTWARE The evaluation board comes with software and an USB cable to link the evaluation board to the PC. The evaluation software was developed with Lab Windows®/CVI™, a software development package from national Instruments. The evaluation software is available for download on the Cirrus Logic web site at http://www.cirrus.com/industrialsoftware and was designed to run under Windows 2000™ or Windows XP®. 2.
CDB5461AU 2.3.1 Setup Setup allows user to establish a USB communication connection with CDB5461AU board or select a pre-saved data file for further analysis. If the USB is selected, the evaluation software will poll the CDB5461AU, verifying the serial communication link is ready. At this point USB is checked indicating that the PC has successfully communicated with CDB5461AU evaluation board, and device and micro-code version information are read from the board and displayed on the screen. See Figure 3.
CDB5461AU Figure 5. Selecting a Data File for Further Analysis 2.3.2 Quit Quit allows the user to exit the evaluation software. Upon selecting Quit, a message windows appears that verifies whether exiting the evaluation software is desired. See Figure 6. Figure 6.
CDB5461AU 2.3.3 Menu Except for the Start-up window, Menu allows 7 selection options, Setup window, Calibration window, Conversion window, Pulse Rate window, Data Collection window, EEPROM window and Debug window. Each window provides a means to evaluate the different functionalities and performances of the CS5461A. See Figure 7. Figure 7. Menu Pull-down Options 2.4 Setup Window The evaluation software provides access to the CS5461A's internal registers in the Setup window (Figure 8).
CDB5461AU Figure 8. Setup Window 2.4.1 Refresh Screen Button The Refresh Screen button will update the contents of the screen by reading all the register values from the CS5461A device. It is a good idea to press the Refresh Screen button when entering the Setup window, or after modifying any registers to reflect the current status of the device. 2.4.2 Reset DUT Button The Reset DUT button will hardware reset the CS5461A. The CS5461A will perform a reset as discussed in the CS5461A data sheet.
CDB5461AU 2.4.4 Configuration Register Panel In the Configuration Register panel, the contents of the Configuration register can be modified by typing a hexadecimal value in the HEX: field, or by changing any of the values below the HEX: field to the desired settings. Although the CDB5461AU software allows the user to modify any of the bits in the Configuration register, changing certain bits may cause the software and board to behave erratically.
CDB5461AU 2.5 Calibration Window The Calibration window is used to display and write to the CS5461A Offset and Gain calibration registers. The user is also able to initiate the CS5461A's calibration sequences that are used to set the calibration values. Both AC and DC calibrations can be run for offset and gain, for either the voltage channel or the current channel, or both simultaneously. The user should refer to the CS5461A data sheet for more details on calibration.
CDB5461AU 2.5.2.1 Offset Calibrations 1. Ground the channel(s) you want to calibrate directly at the channel header(s). J17 and J22 for the voltage channel, and J24 and J26 for the current channel. The channel(s) could also be grounded directly at the screw terminals. 2. Press the corresponding AC or DC offset calibrate button(s) (Cal V, Cal I, or Cal Both) in the Offset panel. 3. The calibration value(s) will automatically update when the calibration is completed. 2.5.2.2 Gain Calibrations 1.
CDB5461AU 2.6 Conversion Window The Conversion window shown in Figure 10 allows the user to see the results of single and continuous conversions, perform data averaging, utilize the power-saving modes of the CS5461A, and reset the CS5461A's serial port. The Conversion window can be accessed by pulling down the Menu option, and selecting Conversion Window, or by pressing . Figure 10. Conversion Window 2.6.1 Single Conversion Button By pressing this button, single conversions will be performed.
CDB5461AU 2.6.4 Power Up Button This button is used to send the Power-up/Halt command to the CS5461A. The device will return to normal operating mode and halt any conversions that are being performed at the time. 2.6.
CDB5461AU 2.7.3 Start Button When the Start button is pressed, the CDB5461AU will capture pulse rate data according to the values in the Integration Seconds and Periods to Average fields. After each integration period, the Pulse Count and Frequency columns will be updated. The Average Freq. and Standard Deviation columns will only be updated after all the integrations have been collected. The software stops collecting data when the user presses the Stop button, or when the data collection is complete.
CDB5461AU 2.8.3 Collect Button This button will collect data from the CS5461A device to be analyzed in the plot area. See the section on Collecting Data Sets for more information. 2.8.4 Output Button This button will bring up a window in which the user can output the data to a file for later use, print out a plot, or print out the entire screen. When saving data, only the data channel being displayed on the plot will be saved to a file. 2.8.
CDB5461AU 2.8.7.6 Cycle Count The value in Cycle Count field will be written to the CS5461A’s Cycle Count register. Cycle Count determines the length of one computation cycle. Cycle Count should be selected appropriately according to the Data to Collect selection. For example, if the Data to Collect is instantaneous Current, Voltage, or Power, it is better to set Cycle Count to 1.
CDB5461AU 2.8.11 Histogram Information The following is a description of the indicators associated with Histogram analysis. Histograms can be plotted in the Data Collection window by setting the Time Domain / FFT / Histogram selector to Histogram (Figure 13). Figure 13. Histogram Analysis 2.8.11.1 Bin Displays the x-axis value of the cursor on the Histogram. 2.8.11.2 Magnitude Displays the y-axis value of the cursor on the Histogram. 2.8.11.3 Mean Indicator for the mean of the data sample set.
CDB5461AU 2.8.11.4 STD_DEV Indicator for the standard deviation of the collected data set. The standard deviation is calculated using the following formula: n–1 StdDev = 2.8.11.5 ( Xi – Mean ) ∑ i=0 2 --------------------------------------------n Variance Indicator for the variance of the current data set. The variance is calculated using the following formula: n–1 ∑ ( Xi – Mean ) 2 i=0 Var = --------------------------------------------n 2.8.11.
CDB5461AU 2.8.12 Frequency Domain Information The following describe the indicators associated with FFT (Fast Fourier Transform) analysis. FFT data can be plotted in the Data Collection window by setting the Time Domain / FFT / Histogram selector to FFT (Figure 14). Figure 14. FFT Analysis 2.8.12.1 Frequency Displays the x-axis value of the cursor on the FFT display. 2.8.12.2 Magnitude Displays the y-axis value of the cursor on the FFT display. 2.8.12.
CDB5461AU 2.8.12.6 SNR Indicator for the signal-to-noise ratio, first 4 harmonics are not included (decibels). 2.8.12.7 Fs-Pdb Indicator for the full-scale to signal ratio (decibels). 2.8.13 Time Domain Information The following controls and indicators are associated with Time Domain analysis. Time Domain data can be plotted in the Data Collection window by setting the Time Domain / FFT / Histogram selector to Time Domain (Figure 15). Figure 15. Time Domain Analysis 2.8.13.
CDB5461AU 2.8.13.4 Minimum Indicator for the minimum value of the collected data set. 2.9 EEPROM Window CDB5461AU has an “Auto-boot” Demo feature for the serial EEPROM, which means CDB5461AU can operate independently without connecting to a PC. The CDB5461AU GUI software also provides an EEPROM window for reading/writing the serial EEPROM (Figure 16). Figure 16. EEPROM Window The Bytes to Read/Write field allows the user to define the number of bytes to be read or written. 2.9.
CDB5461AU Figure 17.
CDB5461AU Figure 18. Analog Inputs 3.
Figure 19.
Figure 20.
Figure 21.
CDB5461AU LAYOUT Figure 22. Top Silk Screen 4.
Figure 23.
Figure 24.
Figure 25.
CDB5461AU Contacting Cirrus Logic Support For all product questions and inquiries contact a Cirrus Logic Sales Representative. To find one nearest you go to www.cirrus.com IMPORTANT NOTICE Cirrus Logic, Inc. and its subsidiaries ("Cirrus") believe that the information contained in this document is accurate and reliable. However, the information is subject to change without notice and is provided "AS IS" without warranty of any kind (express or implied).
