CS5490
1. OVERVIEW
The CS5490 is a CMOS power measurement integrated circuit that uses two
analog-to-digital
converters to measure line voltage and current. The CS5490 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. A separate analog-to-digital converter is used for on-chip
temperature measurement.
The CS5490 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 input to accommodate different types of current sensors. The
CS5490’s two 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±.
The digital output (DO) provides a variety of output signals and, depending on the mode selected,
provides energy pulses, zero-crossings, or other choices.
The CS5490 includes a UART serial host interface to an external microcontroller. The UART signals
include serial data input (RX) and serial data output (TX).
DS982F2
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APEX [ CIRRUS LOGIC ]
