Cirrus Logic CS5480 - Manual (Page 5)

CS5480
DS980F3 5
1. OVERVIEW
The CS5480 is a CMOS power measurement integrated circuit that uses three  analog-to-digital
converters to measure line voltage, two currents and temperature. It calculates active, reactive, and
apparent power as well as RMS voltage and current and peak voltage and current. It handles other
system-related functions, such as energy pulse generation, voltage sag and swell, overcurrent and
zero-crossing detection, and line frequency measurement.
The CS5480 is optimized to interface to current transformers, shunt resistors, or Rogowski coils for
current measurement and to resistive dividers or voltage transformers for voltage measurement. Two
full-scale ranges are provided on the current inputs to accommodate different types of current sensors.
The CS5480’s three differential inputs have a common-mode input range from analog ground (GNDA) to
the positive analog supply (VDDA).
An on-chip voltage reference (nominally 2.4 volts) is generated and provided at analog output, VREF±.
Three digital outputs (DO1, DO2, and DO3) provide a variety of output signals, and depending on the
mode selected, energy pulses, zero-crossings, or other choices.
The CS5480 includes a UART/SPI™ serial host interface to an external microcontroller. The serial select
(SSEL) pin is used to configure the serial port to be a SPI or UART. SPI signals include serial data input
(SDI), serial data output (SDO), and serial clock (SCLK). UART signals include serial data input (RX) and
serial data output (TX). A chip select (CS) signal allows multiple CS5480s to share the same serial
interface with the microcontroller.