Cirrus Logic CS5484 - Manual (Page 5)

CS5484
DS981F3 5
1. OVERVIEW
The CS5484 is a CMOS power measurement integrated circuit using four  analog-to-digital converters
to measure two line voltages and two currents. Optionally, voltage2 channel can be used for temperature
measurement. 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 CS5484 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 CS5484’s four differential inputs have a common-mode input range from analog ground (GNDA) to
the positive analog supply (VDDA).
An on-chip voltage reference (typically 2.4 volts) is generated and provided at analog output, VREF±.
Four digital outputs (DO1, DO2, DO3, and DO4) provide a variety of output signals, and depending on the
mode selected, provide energy pulses, zero-crossings, or other choices.
The CS5484 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 CS5484s to share the same serial
interface with the microcontroller.