
ILA19002
Korzhenevskogo 12, Minsk, 220108, Republic of
Belarus
Fax: +375 (17) 278 28 22,
Phone: +375 (17) 278 07 11, 212 24 70, 212 24 61,
212 69 16
E-mail: office@bms.by
URL: www.bms.by
5
FUNCTIONAL DESCRIPTION
The ILA19002 is a CMOS mixed signal Analog/Digital integrated circuit, which performs
power/energy calculations across a power range of 1000:1, to an overall accurancy of better
than Class 1.
The integrated circuit includes all the required functions for 1-phase power and energy
measurement such as two oversampling A/D converters for the voltage and current sense
inputs, power calculation and energy integration. Internal offsets are eliminated through the
use of cancellation procedures. The ILA19002 generates pulses, the frequency of which is
proportional to the power consumption. The pulse rate follows the instantaneous power
consumption measured. Direction information is also provided.
A voltage zero crossover signal, relevant to the positive going half cycle, is available on pin
FMO. This signal can be used to synchronise circuit breaker switching.
1. Power Calculation
In the Application Circuit (Figure 1), the voltage drop across the shunt will be between
0 and 16mV
RMS
(0 to 80A through a shunt resistor of 200μ
). This voltage is
converted to a current of between 0 and 16μA
RMS
, by means of resistors R
1
and R
2
.
The current sense input saturates at an input current of ±25μA peak.
For the voltage sensor input, the mains voltage (230VAC) is divided down through
a divider to 14V. The current into the A/D converter input is set at 14μA
RMS
at nominal
mains voltage, via resistor R4 (1M
)
.
In this configuration, with a mains voltage of 230V and a current of 80A, the output
frequency of the ILA19002 power meter chip at FOUT is 1.16kHz. In this case 1 pulse
will correspond to an energy consumption of 18.4kW/1160Hz = 15.9Ws.
2. Analog Input Configuration
The input circuitry of the current and voltage sensor inputs are illustrated below.
These inputs are protected against electrostatic discharge through clamping diodes.
The feedback loops from the outputs of the amplifiers A
I
and A
V
generate virtual
shorts on the signal inputs. Exact duplications of the input currents are generated
for the analog signal processing circuitry.
3. Electrostatic Discharge (ESD) Protection
The ILA19002 integrated circuit's inputs/outputs are protected against ESD
4. Power Consumption
The power consumption rating of the ILA19002 integrated circuit is less than 25mW.
5. Pulse Output Signals
The diagram below shows the behavior of the instantaneous pulse output, FOUT,
with respect to the power consumption.