90E36A
Preliminary Information*
*Notice: The information in this document is subject to change without notice
Poly-Phase High-Performance
Wide-Span Energy Metering IC
FEATURES
Metering Features
•Metering features fully in compliance with the requirements of
IEC62052-11, IEC62053-22 and IEC62053-23, ANSI C12.1 and
ANSI C12.20; applicable in class 0.5S or class 1 poly-phase
watt-hour meter or class 2 poly-phase var-hour meter.
•Accuracy of ±0.1% for active energy and ±0.2% for reactive
energy over the dynamic range of 6000:1.
•Temperature coefficient is 6 ppm/°C (typical) for on-chip refer-
ence voltage.
•Single-point calibration on each phase over the whole dynamic
range for active energy; no calibration needed for reactive/
apparent energy.
•±1°C (typical) temperature sensor accuracy.
•Electrical parameters measurement: less than ±0.5% fiducial
error for Vrms, Irms, mean active/ reactive/ apparent power, fre-
quency, power factor and phase angle.
•Active (forward/reverse), reactive (forward/reverse), apparent
energy with independent energy registers. Active/ reactive/
apparent energy can be output by pulse or read through energy
registers to adapt to different applications.
•Programmable startup and no-load power threshold, special
designed of startup and no-load circuits to eliminate crosstalk
among phases achieving better accuracy especially at low
power conditions.
•Dedicated ADC and different gains for phase A/B/C and Neutral
line current sampling circuits. Current sampled over current
transformer (CT) or Rogowski coil (di/dt coil); phase A/B/C volt-
age sampled over resistor divider network or potential trans-
former (PT).
•Programmable power modes: Normal mode (N mode), Idle
mode (I mode), Detection mode (D mode) and Partial Measure-
ment mode (M mode).
•Fundamental (CF3, 0.2%) and harmonic (CF4, 1%) active
energy with dedicated energy and power registers.
•Total Harmonic Distortion (THD) and Discrete Fourier Transform
(DFT) functions for 2 ~ 32 order harmonic component. THD and
DFT results available in SPI accessible registers. Both voltage
and current of all phases processed within the same time period.
•Event detection: sag, phase loss, reverse voltage/ current phase
sequence, reverse flow, calculated neutral line current INC over-
current sampled neutral line current INS overcurrent and THD+N
over-threshold.
Other Features
•3.3V single power supply. Operating voltage range: 2.8V~3.6V.
Metering accuracy guaranteed within 3.0V~3.6V.
•Four-wire SPI interface with Direct Memory Access (DMA) mode
to stream out 7-channel ADC raw data.
•Parameter diagnosis function and programmable interrupt output
of the IRQ interrupt signals and the WarnOut signal.
•Programmable voltage sag detection and zero-crossing output.
•CF1/CF2/CF3/CF4 output active/ reactive/ apparent energy
pulses and fundamental/ harmonic energy pulses respectively.
•Crystal oscillator frequency: 16.384 MHz. On-chip two capacitors
and no need of external capacitors.
•TQFP48 package.
•Operating temperature: -40°C ~ +85°C.
APPLICATION
•Poly-phase energy meters of class 0.5S and class 1 which are
used in three-phase four-wire (3P4W, Y0) or three-phase three-
wire (3P3W, Y or Δ) systems.
•Data Acquisition Terminal.
•Power monitoring instruments which need to measure voltage,
current, THD, DFT, mean power, etc.
GENERAL DESCRIPTION
The 90E36A is a poly-phase high performance wide-dynamic range
metering IC. The 90E36A incorporates 7 independent 2nd order sigma-
delta ADCs, which could be employed in three voltage channels (phase
A, B and C) and four current channels (phase A, B, C and neutral line) in
a typical three-phase four-wire system.
The 90E36A has an embedded DSP which executes calculation of
active energy, reactive energy, apparent energy, fundamental and har-
monic active energy over ADC signal and on-chip reference voltage.
The DSP also calculates measurement parameters such as voltage and
current RMS value as well as mean active/reactive/apparent power.
A four-wire SPI interface is provided between the 90E36A and the
external microcontroller. In addition, DMA mode can be used for 7-chan-
nel ADC raw data access, offering more flexibility in system application.
The 90E36A is suitable for poly-phase multi-function meters which
could measure active/reactive/apparent energy and fundamental/har-
monic energy either through four independent energy pulse outputs
CF1/CF2/CF3/CF4 or through the corresponding registers.
With the on-chip THD and DFT engine, all phases' THD and DFT
results can be directly accessed through related registers, thus simplify-
ing hardware design in Data Acquisition Terminals.
The ADC and auto-temperature compensation technology for refer-
ence voltage ensure the 90E36A's long-term stability over variations in
grid and ambient environment conditions.