SA9602E Datasheet, PDF (7/14 Pages) Sames – SINGLE PHASE UNIDIRECTIONAL POWER/ENERGY METERING IC WITH INSTANTANEOUS PULSE OUTPUT

SA9602E
The output on pin FOUT is a pulse density signal representing the instantaneous power/
energy measurement. The minimum timing characteristics are shown in the following
diagram.
71us
DR-01151
71us min.
TYPICAL APPLICATIONS
In the Application Circuits (Figures 1 and 2), the components required for power metering
applications, are shown.
In Figure 1 a shunt resistor is used for current sensing. In this application, the circuitry
requires a +2.5V, 0V, -2.5V DC supply.
In the case of Figure 2, when using a current transformer for current sensing, a +5V, 0V
DC supply is sufficient.
The most important external components for the SA9602E integrated circuit are:
R , R and RSH are the resistors defining the current level into the current sense input. The
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values should be selected for an input current of 16µA_RMS into the SA9602E at maximum
line current.
Values for RSH of less than 200µΩ should be avoided.
R₁ = R₂ = (I_L/16µA_RMS) * R_SH/2
Where I
L
= Line current
RSH = Shunt resistor/termination resistor
R , R and R set the current for the voltage sense input. The values should be selected
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4
so that the input current into the voltage sense input (virtual ground) is set to 14µA .
RMS
R₇ defines all on-chip bias and reference currents. With R₇ = 24kΩ, optimum conditions
are set. R may be varied within ±10% for calibration purposes. Any change to R will affect
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the output quadratically (i.e.: R = +5%, f = +10%).
7
P
The formula for calculating the output frequency is given below:
f = 11.16 _* FOUTX _* ^FOSC _* ^{II .IV}
3.58MHz I ²
R
Where FOUTX = Normal rated frequency (4Hz or 1160Hz)
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