Cirrus Logic CS5480 - Manual

Copyright  Cirrus Logic, Inc. 2013
(All Rights Reserved)
Cirrus Logic, Inc.
http://www.cirrus.com
CS5480
Three Channel Energy Measurement IC
Features
• Superior Analog Performance with Ultra-low Noise Level &
High SNR
• Energy Measurement Accuracy of 0.1% over 4000:1
Dynamic Range
• Current RMS Measurement Accuracy of 0.1% over 1000:1
Dynamic Range
• 3 Independent 24-bit, 4 th -order, Delta-Sigma Modulators
for Voltage and Current Measurements
• 3 Configurable Digital Outputs for Energy Pulses,
Zero-crossing, or Energy Direction
• Supports Shunt Resistor, CT, & Rogowski Coil Current
Sensors
• On-chip Measurements & Calculations:
- Active, Reactive, and Apparent Power
- RMS Voltage and Current
- Power Factor and Line Frequency
- Instantaneous Voltage, Current, and Power
• Overcurrent, Voltage Sag, and Voltage Swell Detection
• Ultra-fast On-chip Digital Calibration
• Internal Register Protection via Checksum and Write
Protection
• UART/SPI™ Serial Interface
• On-chip Temperature Sensor
• On-chip Voltage Reference (25ppm / °C Typ.)
• Single 3.3V Power Supply
• Ultra-fine Phase Compensation
• Low Power Consumption: <13mW
• Power Supply Configurations
GNDA = GNDD = 0V, VDDA = +3.3V
• 4mm x 4mm, 24-pin QFN Package
ORDERING INFORMATION
See Page 69 .
Description
The CS5480 is a high-accuracy, three-channel, energy mea-
surement analog front end.
The CS5480 incorporates independent, 4
th order, Delta-Sigma
analog-to-digital converters for every channel, reference cir-
cuitry, and the proven EXL signal processing core to provide
active, reactive, and apparent energy measurement. In addi-
tion, RMS and power factor calculations are available.
Calculations are output via configurable energy pulse, or direct
UART/SPI™ serial access to on-chip registers.
Instantaneous current, voltage, and power measurements are
also available over the serial port. Multiple serial options are
offered to allow customer flexibility. The SPI provides higher
speed, and the 2-wire UART minimizes the cost of isolation
where required.
Three configurable digital outputs provide energy pulses, zero-
crossing, energy direction, and interrupt functions. Interrupts
can be generated for a variety of conditions including voltage
sag or swell, overcurrent, and more. On-chip register integrity
is assured via checksum and write protection. The CS5480 is
designed to interface to a variety of voltage and current sen-
sors including shunt resistors, current transformers, and
Rogowski coils.
On-chip functionality makes digital calibration simple and ul-
tra-fast, minimizing the time required at the end of the
customer production line. Performance across temperature is
ensured with an on-chip voltage reference with very low drift.
A single 3.3V power supply is required, and power consump-
tion is very low at <13mW. To minimize space requirements,
the CS5480 is offered in a low-cost, 4mm x 4mm 24-pin QFN
package.
VDDA
GNDA
TX / SDO
RX / SDI
UART/SPI
Serial
Interface
Energy
To
Pulse
Conversion
RESET
Calculation
4th Order 
Modulator
Digital
Filter
HPF
Option
DO1
DO2
Digital
Filter
4th Order 
Modulator
HPF
Option
Temperature
Sensor
VREF+ Voltage
Reference
VDDD
VREF-
System
Clock
IIN2+
IIN2-
PGA
IIN1+
IIN1-
PGA
10x
CS5480
GNDD
CS
SCLK
SSEL
DO3
VIN+
VIN-
Clock
Generator
XIN XOUT
MODE
Digital
Filter
HPF
Option
4th Order 
Modulator
MAR’13
DS980F3