CS5460A_07 Datasheet, PDF (1/54 Pages) Cirrus Logic – Single Phase, Bi-directional Power/Energy IC

CS5460A
Single Phase, Bi-directional Power/Energy IC
Features
z Energy Data Linearity: ±0.1% of Reading
over 1000:1 Dynamic Range.
z On-Chip Functions: (Real) Energy, I ∗ V,
I_RMS and V_RMS, Energy-to-Pulse
Conversion
z Smart “Auto-boot” Mode from Serial
EEPROM Enables Use without MCU.
z AC or DC System Calibration
z Mechanical Counter/Stepper Motor Driver
z Meets Accuracy Spec for IEC 687/1036, JIS
z Typical Power Consumption <12 mW
z Interface Optimized for Shunt Sensor
z V vs. I Phase Compensation
z Ground-Referenced Signals with Single
Supply
z On-chip 2.5 V Reference (MAX 60 ppm/°C
drift)
z Simple Three-wire Digital Serial Interface
z Watch Dog Timer
z Power Supply Monitor
z Power Supply Configurations
VA+ = +5 V; VA- = 0 V; VD+ = +3.3 V to +5 V
Description
The CS5460A is a highly integrated power mea-
surement solution which combines two ∆Σ
Analog-to-digital Converters (ADCs), high-speed
power calculation functions, and a serial interface
on a single chip. It is designed to accurately mea-
sure and calculate: Real (True) Energy,
Instantaneous Power, I_RMS, and V_RMS for single
phase 2- or 3-wire power metering applications.
The CS5460A interfaces to a low-cost shunt resis-
tor or transformer to measure current, and to a
resistive divider or potential transformer to mea-
sure voltage. The CS5460A features a
bi-directional serial interface for communication
with a microcontroller and a pulse output engine for
which the average pulse frequency is proportional
to the real power. The CS5460A has on-chip func-
tionality to facilitate AC or DC system-level
calibration.
The “Auto-boot” feature allows the CS5460A to
function ‘stand-alone’ and to initialize itself on sys-
tem power-up. In Auto-boot Mode, the CS5460A
reads the calibration data and start-up instructions
from an external EEPROM. In this mode, the
CS5460A can operate without a microcontroller, in
order to lower the total bill-of-materials cost.
VA+
IIN+ PGA
IIN-
x10,x50
4^th Order
∆Σ
Modulator
VIN+
x10
VIN-
VREFIN
x1
2^nd Order
∆Σ
Modulator
VREFOUT
Voltage
Reference
Power
Monitor
RESET
VD+
Digital
Filter
Digital
Filter
System
Clock
/K
High Pass
Filter
Power
Calculation
Engine
(Energy
I*V
I_RMS ,V_RMS )
High Pass
Filter
Clock
Generator
Watch Dog
Timer
Control /
Serial
Interface
Energy-to-
Pulse
Converter
Calibration
SRAM
MODE
CS
SDI
SDO
SCLK
INT
EDIR
EOUT
Cirrus Logic, Inc.
http://www.cirrus.com
VA-
PFMON
XIN XOUT CPUCLK
DGND
Copyright © Cirrus Logic, Inc. 2007
(All Rights Reserved)
NOV ‘07
DS487F4
1