Cirrus Logic CDB5484U User Manual
CDB5484U
CDB5484U Engineering Board and GUI Software
Features
• Standalone Power Meter Application
• Voltage and Current Interfaces
• 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 and Chip Control
– Simplified Register
– Quick Calibration Control
– FFT Analysis
– Time Domain Analysis
– Noise Histogram Analysis
• Voltage Reference Access
®
/CVI® GUI Software
General Description
The CDB5484U is an extensive tool designed to evaluate the
functionality and performance of Cirrus Logic’s CS5484 power/energy measurement device.
Multiple analog input connection options, configuration input filters, direct and isolated digital interfaces, multiple power supply
options, an onboard programmable microcontroller, 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 and control to the onboard CS5484 device. It also includes the function
of raw ADC data collection with time domain, frequency domain,
and histogram analysis.
Schematics in the PADS™ PowerLogic™ format are available
on request.
ORDERING INFORMATION
CDB5484U-Z Evaluation Board
Cirrus Logic, Inc.
http://www.cirrus.com
Copyright Cirrus Logic, Inc. 2012
(All Rights Reserved)
APR’12
DS919DB5
CDB5484U
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 DS919DB5
CDB5484U
TABLE OF CONTENTS
1. HARDWARE .............................................................................................................................................. 5
1.1 Introduction ........................................................................................................................................ 5
1.2 Evaluation Board Overview ................................................................................................................ 5
1.3 Analog Section ................................................................................................................................... 6
1.4 Digital Section .................................................................................................................................... 9
1.5 Power Supply Section ...................................................................................................................... 11
1.6 Typical Sensor Connections ............................................................................................................ 12
1.7 Standalone Meter Application .......................................................................................................... 15
2. SOFTWARE ............................................................................................................................................. 16
2.1 Installation Procedure ...................................................................................................................... 16
2.2 Using the Software ........................................................................................................................... 16
2.3 Start-up Window ............................................................................................................................... 17
2.4 Connect Menu .................................................................................................................................. 17
2.5 System Menu ................................................................................................................................... 21
2.6 Calibration Window .......................................................................................................................... 25
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
DS919DB5 3
CDB5484U
LIST OF FIGURES
Figure 1. CDB5484U Assembly Drawing and Default Configuration ................................................................ 5
Figure 2. Voltage Channel — Low-voltage Input .............................................................................................. 6
Figure 3. Voltage Channel — High-voltage Input ............................................................................................. 7
Figure 4. Current Channel — Low-voltage Input .............................................................................................. 8
Figure 5. MCU Connection Window ................................................................................................................. 9
Figure 6. Shunt Sensor Power Meter ............................................................................................................. 12
Figure 7. Current Transformer Power Meter................................................................................................... 13
Figure 8. Rogowski Coil Power Meter ............................................................................................................14
Figure 9. Standalone Power Meter Measurements ........................................................................................ 15
Figure 10. GUI Start-up Window..................................................................................................................... 17
Figure 11. Connect to the CDB board Window............................................................................................... 18
Figure 12. Connect Menu Showing Successful USB Connection .................................................................. 18
Figure 13. USB Error Message....................................................................................................................... 18
Figure 14. Connect Menu Showing Serial Connection Options...................................................................... 19
Figure 15. UART Serial Port Selection Window, UART Selected................................................................... 19
Figure 16. SPI Serial Port Selection Window, SPI Selected........................................................................... 19
Figure 17. Unknown Chip ID Error Message .................................................................................................. 20
Figure 18. System Pull-down Options ............................................................................................................ 21
Figure 19. Setup Window ............................................................................................................................... 22
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..................................................................................................... 31
Figure 26. Data Collection Configuration Window .......................................................................................... 31
Figure 27. Histogram Analysis........................................................................................................................ 34
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. Bill of Materials (Page 1 of 2) ........................................................................................................ 38
Figure 33. Bill of Materials (Page 2 of 2) ........................................................................................................ 39
Figure 34. Schematic - Analog Inputs............................................................................................................. 40
Figure 35. Schematic - CS5484 and Socket................................................................................................... 41
Figure 36. Schematic - Microcontroller and USB Interface............................................................................. 42
Figure 37. Top Silkscreen............................................................................................................................... 43
Figure 38. Top Routing ................................................................................................................................... 45
Figure 39. Bottom Routing.............................................................................................................................. 46
Figure 40. Solder Paste Mask ........................................................................................................................ 47
4 DS919DB5
CDB5484U
1. HARDWARE
1.1 Introduction
The CDB5484U evaluation board provides a convenient means of evaluating the CS5484 energy measurement IC. The CDB5484U evaluation board operates from a single USB or 5V power supply. An optional 3.3V power supply input is available for powering the CS5484 directly. The evaluation board
interfaces the CS5484 to a PC via a USB cable. To accomplish this, the board comes equipped with a
C8051F342 microcontroller and a USB interface. Additionally, the CDB5484U GUI software provides
easy access to the internal registers of the CS5484. 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
CS5484, passive anti-aliasing filters, and a high-voltage section with attenuation resistor networks. The
digital section consists of the C8051F342 microcontroller, LCD, test switches, reset circuitry, and 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. CDB5484U Assembly Drawing and Default Configuration
DS919DB5 5
CDB5484U
O VIN1-
O O VIN1-
GND
VIN1-
(Default)
O VIN1+
O O VIN1+
O O VIN1+
GND
Line1
VIN1+
(Default)
O VIN2-
O O VIN2-
VIN2-
GND
(Default)
O VIN2+
O O VIN2+
O O VIN2+
VIN2+
Line2
GND
(Default)
O VIN1-
O O VIN1-
GND
VIN1-
O VIN1+
O O VIN1+
O O VIN1+
GND
Line1
VIN1+
O VIN2-
O O VIN2-
VIN2-
GND
O VIN2+
O O VIN2+
O O VIN2+
VIN2+
Line2
GND
O VIN1-
O O VIN1-
GND
VIN1-
O VIN1+
O O VIN1+
O O VIN1+
GND
Line1
VIN1+
O VIN2-
O O VIN2-
VIN2-
GND
O VIN2+
O O VIN2+
O O VIN2+
VIN2+
Line2
GND
O VIN1-
O O VIN1-
GND
VIN1-
O VIN1+
O O VIN1+
O O VIN1+
GND
Line1
VIN1+
O VIN2-
O O VIN2-
VIN2-
GND
O VIN2+
O O VIN2+
O O VIN2+
VIN2+
Line2
GND
VIN1+/VIN2+
VIN1-/VIN2-
250 mVp
CDB5484U
CS5484
J3/J2
J6/J10
J11/J9
C4/C8
0.027UF
C9/C7
0.027UF
R6/R4
1K
R7/R3
1K
J45/J47
VIN1+/VIN2+
VIN1-/VIN2-
1.3 Analog Section
The analog section of the CDB5484U 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 channel configurations.
1.3.1 Voltage Sensor Connection
There are three input signal options for the voltage channel inputs (VIN1±, VIN2±) which include an external low-voltage signal (via screw terminals or XLR connections), high-voltage line inputs, or GND.
Table 1 illustrates the options available.
Table 1. Voltage Channel Input Signal Selection
INPUT Description J11 J6 J9 J10
Selects External
VIN1± or VIN2±
VIN1± or VIN2±
Low-voltage Fully
Differential Signal
Selects External
Low-voltage Single-ended Signal
GND
High Voltage
Line1 or Line2
Selects Grounding
the Input
Selects External
High-voltage AC
Line Signal
The CDB5484U evaluation board provides screw-type terminals (J3 and J2) or XLR connectors (J30 and
J29) to connect low-voltage input signals to the voltage channels (see Figure 2). The screw terminals are
labeled as VIN1+ / VIN1- and VIN2+ / VIN2-. An R-C network at each channel input provides a simple
configurable anti-alias filter. By installing jumpers on J6 to position VIN1+, J11 to position VIN1-, J10 to
position VIN2+, and J9 to position VIN2-, the input voltage signal is supplied from the screw terminals or
XLR connections.
6 DS919DB5
Figure 2. Voltage Channel — Low-voltage Input
CDB5484U
GND
LINE1/LINE2
CS5484
CDB5484U
NEUTRAL
LINE
J4/J5
J11/J9
J6/J10
R5/R10
1K
C9/C7
0.027UF
C4/C8
0.027UF
R7/R3
1K
R6/R4
1K
R8/R16
422K
R12/R17
422K
R14/R18
422K
R15/R19
422K
J45/J47
VIN1-/VIN2-
VIN1+/VIN2+
1k
4422k1k+
------------------------- ---------------
1
1689
-------------
=
300Vrms
250mVp
2
-----------------------
1689=
The CDB5484U evaluation board provides screw-type terminals (J4 and J5) to connect high-voltage line
inputs. By installing jumpers on J6 to position LINE1, J10 to position LINE2, J11 to position GND, and J9
to position GND, the input voltage signal is supplied from the high-voltage inputs. Extreme care should be
used when connecting high-voltage signals to the CDB5484U evaluation board (see Figure 3).
Figure 3. Voltage Channel — High-voltage Input
The default attenuation networks provide the following attenuation:
With the CS5484 input range of 250mVp at a maximum AC line input of:
is acceptable. It is recommended to apply a 10% margin for the AC line input (270Vrms).
The CDB5484U evaluation board provides input shorting options for calibration and noise performance
measurements. With a jumper on J6, J11, J10, and J9 in the GND position, the inputs are connected to
analog ground (GND).
DS919DB5 7
CDB5484U
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
CS5484
CDB5484U
250 mV
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
illustrates 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
The CDB5484U evaluation board provides two input signal options for current channels (IIN1±, IIN2±):
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.
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 CDB5484U 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).
8 DS919DB5
CDB5484U
U
A
S
P
Low
s
U
A
(4800 B
a
RT
I
peed
RT
ud Max)
J16
Ƒ UART
ż SSEL
ż SPI
(default)
Ƒ UART
ż SSEL
ż SPI
Ƒ UART
ż SSEL
ż SPI
Ƒ
ż
ż
(
d
Ƒ
ż
ż
Ƒ
ż
ż
J18
OPTO
RX
DIGITAL
efault)
OPTO
RX
DIGITAL
OPTO
RX
DIGITAL
J
Ƒ
O
ż
T
ż
D
(def
a
Ƒ
O
ż
T
ż
D
Ƒ
O
ż
T
ż
D
20
PTO
X
IGITAL
ult)
PTO
X
IGITAL
PTO
X
IGITAL
J50
Ƒ VDD
A
ż EN2
ż GND
(default
)
Ƒ VDD
A
ż EN2
ż GND
Ƒ VDD
A
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 CS5484 with the USB connection to the PC, enabling the GUI software to access all of the CS5484
registers and functions.
1.4.1 Serial Port Selection
Communication to the CS5484 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 CS5484 (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 CDB5484U board.
Table 3. Serial Communication Options
DS919DB5 9
CDB5484U
1.4.2 Interface to Microcontroller
Interface headers J17 and J19 are provided to allow the CDB5484U to be connected to an external energy
registration device or an external microcontroller. Interface header J17 provides direct access to the
CS5484 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 10 for details on signal isolation.
Interface header J19 can be used to connect to the external microcontroller. To connect the CS5484 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 jump-
er (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 except CPUCLK.
1.4.4 Additional Device Pin Access
The CS5484’s digital output pins (DO1, DO2, DO3, and DO4) 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 CS5484 system clock can be connected to an onboard quartz crystal, or an external clock can be
supplied to the CS5484 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.
10 DS919DB5
CDB5484U
Sup
p
Sou
r
US
B
Externa
l
&
US
B
Extern
a
ly
ce
C
S
S
o
O
n
3
R
e
+3.3V
B
l +5V
O
n
3
re
g
5484
urce
Bi
p
J3
-board
.3 V
gulator
inding
Post
+
-board
.3V
ulator
nding
ost
6&J37
U
S
u
J
NC
+
3.3 V
+
NC
N
SB
pply
24
5
Ter
m
J
5V
N
5V
N
C
+
V
inals
27
J
C
Ƒ
V
ż
V
(d
e
C
Ƒ
V
ż
V
5V
Ƒ
V
ż
V
VDDA
J21
DDA
DDA
fault)
Ƒ
+
ż
V
ż
+
(d
DDA
DDA
Ƒ
+
ż
V
ż
+
DDA
DDA
Ƒ
+
ż
V
ż
+
J38
+
3.3V
DDA
3.3V_2
efault)
Ƒ
ż
ż
(
3.3V
DDA
3.3V_2
Ƒ
ż
ż
3.3V
DDA
3.3V_2
Ƒ
ż
ż
3.3V_1
J26
+5V EXT
+5V
+5V USB
default)
+5V EXT
+5V
+5V USB
+5V EXT
+5V
+5V USB
1.5 Power Supply Section
Table 4 illustrates the power supply connections on the evaluation board. The positive analog (VDDA) for
the CS5484 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 CS5484 analog supply current and must be installed.
When connecting the CDB5484U board to the AC line through non-isolated sensors, it is strongly recommended that the CS5484 GND reference is connected to the neutral, the non-isolated current sensor is
connected to the neutral, and the CS5484 is supplied by +3.3V isolated from AC line. The DC-DC converter (U8) provides 1kVDC isolation, while no isolation is provided for the 3.3V 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
DS919DB5 11
CDB5484U
IIN1-/IIN2-
IIN1+/IIN2+
GND
GND
GND
LINE1/LINE2
CS5484
CDB5484U
PHASE
NEUTRAL
J1/J12
J4/J5
J7/J13
J8/J14
J11/J9
J6/J10
R5/R10
1K
C5/C11
0.033UF
C6/C12
0.033UF
C9/C7
0.027UF
C4/C8
0.027UF
R11/R22
NO POP
R1/R21
100
R2/R22
100
R7/R3
1K
R6/R4
1K
R9/R23
NO POP
R13/R24
NO POP
R8/R16
422K
R12/R17
422K
R14/R18
422K
R15/R19
422K
R49/R52 1K
R50/R53 1K
C34/C1
0.033UF
C35/C2
0.033UF
J44/J51
J46/J52
R51/R54
0
J45/J47
J53/J56
J54/J55
SHUNT
IIN1+/IIN2+
IIN1-/IIN2-
VIN1-/VIN2-
VIN1+/VIN2+
1.6 Typical Sensor Connections
The CDB5484U evaluation board provides connections directly to different types of sensors. Flexible onboard filter networks provide a convenient configuration for three common transducers: current shunt, current transformer (CT), or Rogowski coil.
1.6.1 Shunt Power Meter Example
An inexpensive current shunt configuration is easily achievable with the CDB5484U 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 high-voltage
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 CDB5484U 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 CS5484 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
12 DS919DB5
CDB5484U
V
burden
I
burden
R
burden
I
primary
N
------------------
R
burden
==
IIN1-/IIN2-
IIN1+/IIN2+
GND
GND
GND
LINE1/LINE2
CS5484
CDB5484U
PHASE
NEUTRAL
J1/J12
J4/J5
J7/J13
J8/J14
J11/J9
J6/J10
R5/R10
1K
C5/C11
0.033UF
C6/C12
0.033UF
C9/C7
0.027UF
C4/C8
0.027UF
R11/R22
2.2
R1/R21
100
R2/R22
100
R7/R3
1K
R6/R4
1K
R9/R23
1K
R13/R24
1K
R8/R16
422K
R12/R17
422K
R14/R18
422K
R15/R19
422K
R49/R52 1K
R50/R53 1K
C34/C1
0.033UF
C35/C2
0.033UF
J44/J51
J46/J52
R51/R54
0
J45/J47
J53/J56
J54/J55
IIN1+/IIN2+
IIN1-/IIN2-
VIN1-/VIN2-
VIN1+/VIN2+
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
CDB5484U 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 CDB5484U 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 CS5484 input
voltage (V
maximum current input should be 10% less than the maximum channel voltage of 250mVp with I-channel
PGA = 10x. The secondary voltage (V
ondary current. Then the secondary current (I
) that the meter places on the system. The optimum secondary voltage (V
burden
) is determined by converting the primary current to the sec-
burden
) can be converted into a voltage by Ohm's Law.
burden
burden
) at the
The secondary voltage (V
) is sourced to the CS5484 through a simple low-pass, anti-alias filter, and
burden
this voltage should not exceed the 250mVp.
Figure 7. Current Transformer Power Meter
DS919DB5 13
CDB5484U
IIN1-/IIN2-
IIN1+/IIN2+
GND
GND
GND
LINE1/LINE2
CS5484
CDB5484U
PHASE
NEUTRAL
J1/J12
J4/J5
J7/J13
J8/J14
J11/J9
J6/J10
R5/R10
1K
C5/C11
0.033UF
C6/C12
0.033UF
C9/C7
0.027UF
C4/C8
0.027UF
R11/R22
NO POP
R1/R21
100
R2/R22
100
R7/R3
1K
R6/R4
1K
R9/R23
NO POP
R13/R24
NO POP
R8/R16
422K
R12/R17
422K
R14/R18
422K
R15/R19
422K
R49/R52 1K
R50/R53 1K
C34/C1
0.033UF
C35/C2
0.033UF
J44/J51
J46/J52
R51/R54
0
J45/J47
J53/J56
J54/J55
IIN1+/IIN2+
IIN1-/IIN2-
VIN1-/VIN2-
VIN1+/VIN2+
1.6.3 Rogowski Coil Power Meter Example
Rogowski coil power meter can be connected to the CDB5484U 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.
14 DS919DB5
CDB5484U
1.7 Standalone Meter Application
The CDB5484U evaluation board provides a standalone power meter using the CS5484, 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 12 for details on the sensor connections and “Power Supply Section” on page 11 for details on
supply options.
The user should not use the GUI to connect the CDB5484U board. Once the GUI is connected to the
CDB5484U board the standalone power meter function is disabled and the LCD on the CDB5484U will
read "Cirrus Logic CS5484 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. CS5484 Die Temperature
Figure 9. Standalone Power Meter Measurements
DS919DB5 15
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