SA9105A Datasheet, PDF (8/12 Pages) Sames – THREE PHASE UNIDIRECTIONAL POWER/ENERGY METERING IC WITH PULSE OUTPUT

SA9105A
The formula for calculating the Output Frequency (f) is given below:
FOSC (I I ) + (I I ) + (I I )
f = 11.16 _* FOUTX _{* 3.58MHz *} ^{I1 V1}
I2 V2
I3 V3
3
*
I2
R
Where FOUTX = Nominal rated frequency (4Hz, 290Hz or 1160Hz)
FOSC = Oscillator frequency (2MHz ...... 4MHz)
I_I1, I_I2, I_I3 = Input currents for current inputs (16µA at rated)
I_V1, I_V2, I_V3 = Input currents for voltage inputs (14µA at rated)
I_R
= Reference current (typically 50µA)
XTAL is a colour burst TV crystal (f = 3.5795 MHz) for the oscillator. The oscillator
frequency is divided down to 1.7897 MHz on-chip, to supply the digital circuitry and the
A/D converters.
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