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Cirrus Logic
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CDB5480U
User Manual
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Cirrus Logic CDB5480U User Manual

CDB5480U
CDB5480U Engineering Board and GUI Software

Features

• Standalone Power Meter Application
• Low- and High-voltage Sensor Connections
• Adaptable Sensor Filters Onboard
• USB Communication with PC
• UART/SPI Isolated Communication
• Onboard C8051F342 Microcontroller
• Single Supply Operation from USB or an External +5 V DC Supply
• Onboard DC-DC Converter and Regulator
• LCD Power Monitor Display
• LabWindows
– Full Register Setup & Chip Control – Simplified Register Access – Quick Calibration Control – FFT Analysis – Time Domain Analysis – Noise Histogram Analysis
• Voltage Reference Access
®
/CVI® GUI Software
General Description
The CDB5480U is an extensive tool designed to evaluate the functionality and performance of the Cirrus Logic CS5480 power/energy measurement device.
Multiple analog input connection options, configuration input filters, direct and isolated digital interfaces, multiple power supply options, an onboard programmable micro-controller, and visual LEDs with an LCD panel make the board a flexible and powerful customer development tool for various power/energy measurement applications.
The GUI software provides easy and complete access to the onboard CS5480 device. In addition, it includes the function of raw ADC data collection with time domain, frequency domain, and histogram analysis.
Schematics in the PADS™ PowerLogic™ format are available for download at http://www.cirrus.com/en/support
ORDERING INFORMATION
CDB5480U-Z Evaluation Board
.
Cirrus Logic, Inc.
http://www.cirrus.com
Copyright Cirrus Logic, Inc. 2012
(All Rights Reserved)
APR’12
DS893DB5
CDB5480U
IMPORTANT SAFETY INSTRUCTIONS
Read and follow all safety instructions prior to using this demonstration board.
This Engineering Evaluation Unit or Demonstration Board must only be used for assessing IC performance in a laboratory setting. This product is not intended for any other use or incorporation into products for sale.
This product must only be used by qualified technicians or professionals who are trained in the safety procedures associated with the use of demonstration boards.
Risk of Electric Shock
• The direct connection to the AC power line and the open and unprotected boards present a serious risk of electric shock and can cause serious injury or death. Extreme caution needs to be exercised while handling this board.
• Avoid contact with the exposed conductor or terminals of components on the board. High voltage is present on exposed conductor and it may be present on terminals of any components directly or indirectly connected to the AC line.
• Dangerous voltages and/or currents may be internally generated and accessible at various points across the board.
• Charged capacitors store high voltage, even after the circuit has been disconnected from the AC line.
• Make sure that the power source is off before wiring any connection. Make sure that all connectors are well
connected before the power source is on.
• Follow all laboratory safety procedures established by your employer and relevant safety regulations and guidelines, such as the ones listed under, OSHA General Industry Regulations - Subpart S and NFPA 70E.
Suitable eye protection must be worn when working with or around demonstration boards. Always
comply with your employer’s policies regarding the use of personal protective equipment.
All components and metallic parts may be extremely hot to touch when electrically active.
Contacting Cirrus Logic Support
For all product questions and inquiries contact a Cirrus Logic Sales Representative. To find the one nearest to 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). Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, indemnification, and limitation of liability. No responsibility is assumed by Cirrus for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work rights, copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and gives consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This con­sent does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROP­ERTY OR ENVIRONMENTAL DAMAGE ("CRITICAL APPLICATIONS"). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED FOR USE IN AIRCRAFT SYSTEMS, MILITARY APPLICATIONS, PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, AUTOMOTIVE SAFETY OR SECURITY DEVICES, LIFE SUPPORT PRODUCTS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDER­STOOD TO BE FULLY AT THE CUSTOMER'S RISK AND CIRRUS DISCLAIMS AND MAKES NO WARRANTY, EXPRESS, STATUTORY OR IMPLIED, INCLUD­ING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR PARTICULAR PURPOSE, WITH REGARD TO ANY CIRRUS PRODUCT THAT IS USED IN SUCH A MANNER. IF THE CUSTOMER OR CUSTOMER'S CUSTOMER USES OR PERMITS THE USE OF CIRRUS PRODUCTS IN CRITICAL APPLICATIONS, CUSTOMER AGREES, BY SUCH USE, TO FULLY INDEMNIFY CIRRUS, ITS OFFICERS, DIRECTORS, EMPLOYEES, DISTRIBUTORS AND OTHER AGENTS FROM ANY AND ALL LIABILITY, INCLUDING ATTORNEYS' FEES AND COSTS, THAT MAY RESULT FROM OR ARISE IN CONNECTION WITH THESE USES.
Cirrus Logic, Cirrus, the Cirrus Logic logo designs, EXL Core, and the EXL Core logo design are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be trademarks or service marks of their respective owners.
SPI is a trademark of Motorola, Inc.
LabWindows and CVI are registered trademarks of National Instruments, Inc.
Windows, Windows 2000, Windows XP, and Windows 7 are trademarks or registered trademarks of Microsoft Corporation.
PADS and PowerLogic are trademarks of Mentor Graphics Corporation.
2 DS893DB5
CDB5480U

TABLE OF CONTENTS

1. HARDWARE .............................................................................................................................................. 4
1.1 Introduction ........................................................................................................................................ 4
1.2 Evaluation Board Overview ................................................................................................................ 4
1.3 Analog Section ................................................................................................................................... 5
1.4 Digital Section .................................................................................................................................... 8
1.5 Power Supply Selection ................................................................................................................... 10
1.6 Typical Sensor Connections ............................................................................................................ 11
1.7 Standalone Meter Application .......................................................................................................... 14
2. SOFTWARE ............................................................................................................................................. 15
2.1 Installation Procedure ...................................................................................................................... 15
2.2 Using the Software ........................................................................................................................... 15
2.3 Start-up Window ............................................................................................................................... 16
2.4 Connect Menu .................................................................................................................................. 16
2.5 System Menu ................................................................................................................................... 20
2.6 Calibration Window .......................................................................................................................... 24
2.7 Conversion Window ......................................................................................................................... 27
2.8 Cirrus Test Window .......................................................................................................................... 29
Appendix A. Bill Of Materials ..................................................................................................................... 38
Appendix B. Schematics............................................................................................................................. 40
Appendix C. Layer Plots ............................................................................................................................. 43

LIST OF FIGURES

Figure 1. CDB5480U Assembly Drawing & Default Configuration ................................................................... 4
Figure 2. Voltage Channel — Low-voltage Input.............................................................................................. 5
Figure 3. Voltage Channel — High-voltage Input ............................................................................................. 6
Figure 4. Current Channel — Low-voltage Input.............................................................................................. 7
Figure 5. MCU Connection Window ................................................................................................................. 8
Figure 6. Shunt Sensor Power Meter ............................................................................................................. 11
Figure 7. Current Transformer Power Meter .................................................................................................. 12
Figure 8. Rogowski Coil Power Meter ............................................................................................................ 13
Figure 9. Standalone Power Meter Measurements ........................................................................................ 14
Figure 10. GUI Start-up Window .................................................................................................................... 16
Figure 11. Connect to the CDB board Window .............................................................................................. 17
Figure 12. Connect Menu Showing Successful USB Connection .................................................................. 17
Figure 13. USB Error Message ...................................................................................................................... 17
Figure 14. Connect Menu Showing Serial Connection Options ..................................................................... 18
Figure 15. UART Serial Port Selection Window, UART Selected .................................................................. 18
Figure 16. SPI Serial Port Selection Window, SPI Selected .......................................................................... 19
Figure 17. Unknown Chip ID Error Message.................................................................................................. 19
Figure 18. System Pull-down Options ............................................................................................................ 20
Figure 19. Setup Window ............................................................................................................................... 21
Figure 20. Calibration Window ....................................................................................................................... 25
Figure 21. Conversion Window ...................................................................................................................... 27
Figure 22. Cirrus Test Pull-down Options....................................................................................................... 29
Figure 23. Data Collection Window ................................................................................................................ 29
Figure 24. Data Collection UART Error Message........................................................................................... 30
Figure 25. Data Collection Output Window .................................................................................................... 30
Figure 26. Data Collection Configuration Window.......................................................................................... 31
Figure 27. Histogram Analysis........................................................................................................................ 33
Figure 28. FFT Analysis ................................................................................................................................. 34
Figure 29. Time Domain Analysis................................................................................................................... 35
Figure 30. Data Collection to File Window ..................................................................................................... 36
Figure 31. Setup and Test Window ................................................................................................................ 37
Figure 32. Schematic - Analog Inputs ............................................................................................................ 40
Figure 33. Schematic - CS5480 & Socket ...................................................................................................... 41
Figure 34. Schematic - Microcontroller & USB Interface ................................................................................ 42
Figure 35. Top Silkscreen .............................................................................................................................. 43
Figure 36. Top Routing................................................................................................................................... 44
Figure 37. Bottom Routing ............................................................................................................................. 45
Figure 38. Solder Paste Mask ........................................................................................................................ 46
DS893DB5 3
CDB5480U

1. HARDWARE

1.1 Introduction

The CDB5480U evaluation board provides a convenient means of evaluating the CS5480 energy measurement IC. The CDB5480U evaluation board operates from a single USB or 5V power supply. An optional 3.3V power supply input is available for powering the CS5480 directly. The evaluation board interfaces the CS5480 to a PC via a USB cable. To accomplish this, the board comes equipped with a C8051F342 microcontroller and a USB interface. Additionally, the CDB5480U GUI software provides easy access to the internal registers of the CS5480. The software also provides a means to display the on-chip ADC performance in the time domain or frequency domain.

1.2 Evaluation Board Overview

The board is partitioned into two main sections: analog and digital. The analog section consists of the CS5480, passive anti-aliasing filters, and a high-voltage section with attenuation resistor networks. The digital section consists of the C8051F342 microcontroller, LCD, the test switches, the reset circuitry, and the USB interface. The board also has a user-friendly power supply connection. The assembly information and default configurations for jumpers are shown below.
Figure 1. CDB5480U Assembly Drawing & Default Configuration
4 DS893DB5
CDB5480U

O VIN-
O O VIN-
GND
VIN-
(Default)

O VIN+ O O VIN+ O O VIN+
GND
Line
VIN+
(Default)

O VIN- O O VIN-
GND
VIN-

O VIN+ O O VIN+ O O VIN+
GND
Line
VIN+

O VIN- O O VIN-
GND
VIN-

O VIN+ O O VIN+ O O VIN+
GND
Line
VIN+

O VIN- O O VIN-
GND
VIN-

O VIN+ O O VIN+ O O VIN+
GND
Line
VIN+
VIN+
VIN-
250 mVp
CDB5480U
CS5480
J3
J6
J11
C4
0.027UF
C9
0.027UF
R6
1K
R7
1K
J45
VIN+
VIN-

1.3 Analog Section

The analog section of the CDB5480U is highly configurable. Onboard signal conditioning options for the voltage and current channels enable most applications to interface directly to the sensors. The following two sections define the voltage and current channels configurations.

1.3.1 Voltage Sensor Connection

There are three input signal options for the voltage channel input (VIN±): an external low-voltage signal (via screw terminals or XLR connections), high-voltage line input, or GND. Table 1 illustrates the options available.
Table 1. Voltage Channel Input Signal Selection
INPUT Description J11 J6
Selects External
VIN±
VIN±
Low-voltage Fully Differential Signal
Selects External Low-voltage Sin­gle-ended Signal
GND
High Voltage
Line
Selects Grounding
the Input
Selects External
High-voltage AC
Line Signal
The CDB5480U evaluation board provides screw-type terminals (J3) or XLR connectors (J30) to connect the low-voltage input signal to the voltage channel (see Figure 2). The screw terminals are labeled as VIN+ / VIN-. An R-C network at the channel input provides a simple configurable anti-alias filter. By installing jumpers on J6 to position VIN+ and J11 to position VIN-, the input voltage signal is supplied from the screw terminals or XLR connection.
DS893DB5 5
Figure 2. Voltage Channel — Low-voltage Input
CDB5480U
GND
LINE
CS5480
CDB5480U
NEUTRAL
LINE
J4
J11
J6
R5 1K
C9
0.027UF
C4
0.027UF
R7
1K
R6
1K
R8
422K
R12
422K
R14
422K
R15
422K
J45
VIN-
VIN+
1k
4 422k1k+
----------------------------------------
1
1689
-------------
=
300V
rms
250mVp
2
-----------------------
1689=
The CDB5480U evaluation board provides screw-type terminal (J4) to connect to the high-voltage line input. By installing jumpers on J6 to position LINE and J11 to position GND, the input voltage signal is supplied from the high-voltage input. Extreme care should be used when connecting high-voltage signals to the CDB5480U evaluation board (see Figure 3).
Figure 3. Voltage Channel — High-voltage Input
The on-board attenuation network provides the following attenuation:
With the CS5480 input range of 250mVp at maximum AC line input of:
is acceptable. It is recommended to apply a 10% margin for the AC line input (270 V
rms
).
The CDB5480U evaluation board provides input shorting options for calibration and noise performance measurements. With a jumper on J6 and J11 in the GND position, the inputs are connected to analog ground (GND).
6 DS893DB5
CDB5480U

O IIN1+
O O IIN1+
IIN1+
GND
(Default)
O IIN1-
O O IIN1-
GND
IIN1-
(Default)

O IIN2+
O O IIN2+
IIN2+
GND
(Default)

O IIN2-
O O IIN2-
GND
IIN2-
(Default)

O IIN1+
O O IIN1+
IIN1+
GND
O IIN1-
O O IIN1-
GND
IIN1-

O IIN2+
O O IIN2+
IIN2+
GND

O IIN2-
O O IIN2-
GND
IIN2-

O IIN1+
O O IIN1+
IIN1+
GND
O IIN1-
O O IIN1-
GND
IIN1-

O IIN2+
O O IIN2+
IIN2+
GND

O IIN2-
O O IIN2-
GND
IIN2-
IIN1-/IIN2-
IIN1+/IIN2+
GND
GND
CS5480
CDB5480U
250 mVp
J1/J12
J7/J13
J8/J14
C5/C11
0.033UF
C6/C12
0.033UF
R11/R22
NO POP
R1/R21
100
R2/R22
100
R9/R23
NO POP
R13/R24
NO POP
R49/R52 1K
R50/R53 1K
C34/C1
0.033UF
C35/C2
0.033UF
J44/J51
J46/J52
R51/R54
0
J53/J56
J54/J55
IIN1+/IIN2+
IIN1-/IIN2-

1.3.2 Current Sensor Connection

Current input options include an external signal (via screw terminals or XLR connectors) or GND. Table 2 shows the options available.
Table 2. Current Channel Input Signal Selection
INPUT Description J8 J7 J14 J13
Selects External
IIN1± or IIN2±
IIN1± or IIN2±
Low-voltage,
Fully Differential
Signal
Selects External
Low-voltage,
Single-ended
Signal
GND
Selects Grounding
the Input
There are two input signal options for current channels (IIN1±, IIN2±). The CDB5480U evaluation board provides screw-type terminals (J1 and J2) or XLR connectors (J28 and J31) to connect input signals to the current channels. The screw terminals are labeled as IIN1+ / IIN1-, and IIN2+ / IIN2-. An R-C network at each channel input provides a simple configurable anti-alias filter (see Figure 3).
By installing jumpers on J8 to position IIN1+, J7 to position IIN1-, J14 to position IIN2+, and J13 to position IIN2-, the input current signal is supplied from the screw terminals or XLR connectors.
Figure 4. Current Channel — Low-voltage Input
The CDB5480U evaluation board provides input shorting options for calibration and noise performance measurements. With a jumper on J8, J7, J14, and J13 in the GND position, the inputs are connected to analog ground (GND).
DS893DB5 7
CDB5480U
J16 J18 J20 J50
UART
Ƒ UART ż SSEL ż SPI (default)
Ƒ OPTO ż RX ż DIGITAL (default)
Ƒ OPTO ż TX ż DIGITAL (default)
Ƒ VDDA ż EN2 ż GND (default)
SPI
Ƒ UART ż SSEL ż SPI
Ƒ OPTO ż RX ż DIGITAL
Ƒ OPTO ż TX ż DIGITAL
Ƒ VDDA ż EN2 ż GND
Low speed
UART
(4800 Baud Max)
Ƒ UART ż SSEL ż SPI
Ƒ OPTO ż RX ż DIGITAL
Ƒ OPTO ż TX ż DIGITAL
Ƒ VDDA ż EN2 ż GND

1.4 Digital Section

The digital section contains the microcontroller, USB interface, LCD, optical isolation, JTAG header, reset circuitry, and external interface headers (J17 and J19). The microcontroller interfaces the UART or SPI of the CS5480 with the USB connection to the PC, enabling the GUI software to access all of the CS5480 registers and functions.

1.4.1 Serial Port Selection

Communication to the CS5480 is provided through two serial port options — UART or SPI. It is necessary to establish communication with the MCU before establishing a serial port communication protocol with the CS5480 (see Figure 5).
Figure 5. MCU Connection Window
For UART communication, place the SSEL jumper to the UART position via J16, and select UART in the serial port selection window. To enable SPI communications, place the SSEL jumper to the SPI position via J16 and select SPI in the serial port selection window. Table 3 provides the serial communication options on the CDB5480U board.
Table 3. Serial Communication Options
8 DS893DB5
CDB5480U

1.4.2 Interface to Microcontroller

Interface headers J17 and J19 are provided to allow the CDB5480U to be connected to an external energy registration device or an external microcontroller. Interface header J17 provides direct access to the CS5480 pins while interface header J19 provides an isolated connection. It is imperative to use the isolated connection (J19) when high-voltage signals are used. Failure to use isolation can result in damage to components or electrical shock. Refer to “Digital Isolation” on page 9 for details on signal isolation.
Interface header J19 can be used to connect to the external microcontroller. To connect the CS5480 to an external microcontroller, R34, R35, R36, R37, R38, R39, R40, R41, R42, and R43 must be removed from the board.

1.4.3 Digital Isolation

Two types of isolation are provided, including a low-speed optical coupler for UART only and high-speed digital isolation for UART and SPI communication. Default jumper settings provide high-speed digital isolators. To enable high-speed digital isolators, place jumpers (J18 and J20) in the RX to DIGITAL position and TX to DIGITAL position. To enable the high-speed digital isolators, it is also necessary to install jumper (J50) in the VDDA position. To enable low-speed optical UART communication, place jumpers (J18 and J20) in the RX to OPTICAL position and TX to OPTICAL position.
The high-speed digital isolators operate from DC to 150Mbps. The low-speed optical couplers operate to a maximum speed of about 4.8kHz. All the signals supplied to the isolators are available to the MCU.

1.4.4 Additional Device Pin Access

The CS5480’s digital output pins DO1, DO2, and DO3 are routed to LEDs, which provide a simple visual check of the digital output. Jumpers J39, J40, J41, and J42 are equipped at the factory with jumpers to enable the LEDs. The DO1 digital output pin is supplied to the digital isolation using jumper J49.
The MODE pin jumper (J15) should be installed in the VDDA to MODE position.
The CS5480 system clock can be connected to an onboard quartz crystal or an external clock can be supplied to the CS5480 XIN pin though jumper J48. To connect the onboard quartz crystal, install jumper J43 in the XIN to CRYSTAL position. To connect XIN to an external clock, install jumper J43 in the XIN to XIN_EXT position.
DS893DB5 9
CDB5480U
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+5V EXT +5V +5V USB
+5V EXT +5V +5V USB

1.5 Power Supply Selection

Table 4 illustrates the power supply connections on the evaluation board. The positive analog (VDDA) for the CS5480 can be supplied using the +3.3V binding post (J36 and J37) or the onboard +3.3V regulator. Jumper J38 allows the VDDA supply to be sourced from the +3.3V binding post (J37) or the regulated +3.3V supply. The DC-DC converter (U8) powers the onboard +3.3V regulator. Jumper J26 allows the +5V supply to be sourced from either the +5V EXT screw connector (J27) or the +5V USB supply. The +5V supplies the power for the microcontroller (8051_REGIN) and the DC-DC converter (U8). Jumper J21 is used to measure the CS5480 analog supply current and must be installed.
When connecting the CDB5480U board to the AC line through non-isolated sensors, it is strongly recommended that the CS5480 GND reference is connected to the neutral, the non-isolated current sensor is connected to the neutral, and the CS5480 is supplied by +3.3V isolated from the AC line. The DC-DC converter (U8) provides 1kVDC isolation, while no isolation is provided for the 3.3 V binding post connections. If +3.3V is used from the binding post, then the external 3.3VDC power supply must be isolated from the AC line. To prevent electric shock and damages, always use an isolated power source.
Table 4. Power Supply Selection
10 DS893DB5
CDB5480U
IIN1-/IIN2-
IIN1+/IIN2+
GND
GND
GND
LINE
CS5480
CDB5480U
PHASE
NEUTRAL
J1/J12
J4
J7/J13
J8/J14
J11
J6
R5 1K
C5/C11
0.033UF
C6/C12
0.033UF
C9
0.027UF
C4
0.027UF
R11/R22
NO POP
R1/R21
100
R2/R22
100
R7
1K
R6
1K
R9/R23
NO POP
R13/R24
NO POP
R8
422K
R12
422K
R14
422K
R15
422K
R49/R52 1K
R50/R53 1K
C34/C1
0.033UF
C35/C2
0.033UF
J44/J51
J46/J52
R51/R54
0
J45
J53/J56
J54/J55
SHUN T
IIN1+/IIN2+
IIN1-/IIN2-
VIN-
VIN+

1.6 Typical Sensor Connections

The CDB5480U evaluation board provides connections directly to several types of sensors. Flexible onboard filter networks provide a convenient configuration for three common transducers, including current shunt, current transformer (CT), or Rogowski coil.

1.6.1 Shunt Power Meter Example

A low-cost current shunt configuration is easily achievable with the CDB5480U evaluation board. Figure 6 depicts the voltage and current connections for a shunt sensor and its associated filter configurations.
It is strongly recommended that a low-side (neutral path) current shunt is used — especially in high­voltage situations. Make sure that all signals are well connected before the power source is turned on. Extreme care should be taken when connecting high-voltage signals to the CDB5480U evaluation board.
In this configuration it is unnecessary to use a burden resistor. A single anti-alias filter is all that is required for the current channel. Below the filter corner frequency, the CS5480 inputs will see the same voltage that is across the shunt. Therefore, the shunt voltage should be kept below the maximum of 50mVp with I-Channel PGA = 50x. A 10% margin is recommended for the shunt voltage (45mVp).
Figure 6. Shunt Sensor Power Meter
DS893DB5 11
CDB5480U
V
burden
I
burden
R
burden
I
primary
N
------------------
R
burden
==
IIN1-/IIN2-
IIN1+/IIN2+
GND
GND
GND
LINE
CS5480
CDB5480U
PHASE
J1/J12
J4
J7/J13
J8/J14
J11
J6
R5 1K
C5/C11
0.033UF
C6/C12
0.033UF
C9
0.027UF
C4
0.027UF
R11/R22
2.2
R1/R21
100
R2/R22
100
R7
1K
R6
1K
R9/R23
1K
R13/R24
1K
R8
422K
R12
422K
R14
422K
R15
422K
R49/R52 1K
R50/R53 1K
C34/C1
0.033UF
C35/C2
0.033UF
J44/J51
J46/J52
R51/R54
0
J45
J53/J56
J54/J55
IIN1+/IIN2+
IIN1-/IIN2-
VIN-
VIN+

1.6.2 Current Transformer Power Meter Example

A slightly more expensive option is to use a current transformer (CT) to connect the AC current to the CDB5480U evaluation board. Figure 7 depicts the voltage and current connections for a CT sensor and its associated filter configurations.
NEVER “open circuit” a CT. Make sure that all signals are well connected before the power source is turned on. Extreme care should be taken when connecting high-voltage signals to the CDB5480U evaluation board.
The burden resistor (R11/R22) is necessary in a CT application to convert the secondary current into voltage. Knowledge of the current transformers turns ratio (N) is key to determining the proper CS5480 input voltage (V the maximum current input should be 10% less than the maximum channel voltage of 250mVp with I­channel PGA = 10x. The secondary voltage (V the secondary current. Then the secondary current (I Law.
) that the meter places on the system. The optimum secondary voltage (V
burden
) is determined by converting the primary current to
burden
) can be converted into a voltage by Ohm's
burden
burden
) at
The secondary voltage (V
) is sourced to the CS5480 through a simple low-pass, anti-alias filter, and
burden
this voltage should not exceed the 250mVp.
12 DS893DB5
Figure 7. Current Transformer Power Meter
CDB5480U
IIN1-/IIN2-
IIN1+/IIN2+
GND
GND
GND
LINE
CS5480
CDB5480U
PHASE
NEUTRAL
J1/J12
J4
J7/J13
J8/J14
J11
J6
R5 1K
C5/C11
0.033UF
C6/C12
0.033UF
C9
0.027UF
C4
0.027UF
R11/R22
NO POP
R1/R21
100
R2/R22
100
R7
1K
R6
1K
R9/R23
NO POP
R13/R24
NO POP
R8
422K
R12
422K
R14
422K
R15
422K
R49/R52 1K
R50/R53 1K
C34/C1
0.033UF
C35/C2
0.033UF
J44/J51
J46/J52
R51/R54
0
J45
J53/J56
J54/J55
IIN1+/IIN2+
IIN1-/IIN2-
VIN-
VIN+

1.6.3 Rogowski Coil Power Meter Example

Rogowski coil power meter can be easily connected to the CDB5480U evaluation board. Figure 8 shows the voltage and current connections for the Rogowski sensor and its associated filter configurations.
Figure 8. Rogowski Coil Power Meter
For more information, see AN365: Using the CS5480/84/90 Energy Measurement IC with Rogowski Coil Current Sensors.
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CDB5480U

1.7 Standalone Meter Application

The CDB5480U evaluation board provides a standalone power meter using the CS5480, MCU, and LCD. The user can enable the power meter by connecting the sensors to the analog inputs, providing power to the board, and resetting the MCU by pressing the RESET switch. Refer to “Typical Sensor Connections” on page 11 for details on the sensor connections and “Power Supply Selection” on page 10 the details on supply options.
The user should not use the GUI to connect the CDB5480U board. If the GUI is connected to the CDB5480U board the standalone power meter function is disabled and the LCD on the CDB5480U will read "Cirrus Logic CS5480 Eval GUI". To re-enable the standalone power meter feature, close the GUI software. The standalone power meter feature will initially show the voltage channels’ RMS register values:
V1rms = N.NNNNN and V2rms = N.NNNNN.
By clicking the onboard switch S2, the standalone power meter will display the following measurement results:
1. RMS Voltage
2. RMS Current
3. Average Active Power
4. Average Reactive Power
5. Average Apparent Power
6. Power Factors
7. Total Active Power
8. Total Reactive Power
9. Total Apparent Power
10. Fundamental Frequency
11. CS5480 die Temperature
Figure 9. Standalone Power Meter Measurements
14 DS893DB5

2. SOFTWARE

CDB5480U
The evaluation board comes with software and a USB cable to link the evaluation board to the PC. The evaluation software was developed with LabWindows tional Instruments. The evaluation software is designed to run with Windows XP™ and Windows 7™. The following procedure is based on Windows XP.
®
/CVI®, a software development package from Na-

2.1 Installation Procedure

Follow the steps below to install the GUI:
1. Access the following web site: http://www.cirrus.com/en/support
2. Navigate to the CDB5480U software link under Energy Measurement. The Software License web page is displayed.
3. To agree with the terms and conditions, click the Agree button. The File Download window is dis­played.
4. Click the Save button. The Save As window is displayed.
5. Select a location to store the compressed folder.
6. Click the Save button. The Download complete window is displayed.
7. Click the Open Folder button. The location where the compressed folder is stored is displayed.
8. Right-click on the compressed folder, and click Extract All.
9. Select a location to extract the files.
.
10. Navigate to the location where the extracted files are stored and double-click on the setup.exe file.
11. Click the Install button, and follow the installation instructions.
12. Execute the GUI using Section 2.1.1 Executing the GUI.

2.1.1 Executing the GUI

1. From the Start menu, click All Programs.
2. Click Cirrus Energy Measurement Evaluation (CDB5480U).
3. Click CDB5480U. The GUI is launched.

2.2 Using the Software

Before launching the software, check all jumper settings on the CDB5480U evaluation board as described in “Evaluation Board Overview” on page 4, and connect the board to an open USB port on the PC using the provided cable. Once the board is powered on, the software program can be launched.
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