SA9105A
The formula for calculating the Output Frequency (f) is given below:
FOSC
(I
I1
I
V1
) + (I
I2
I
V2
) + (I
I3
I
V3
)
f = 11.16 * FOUTX *
3.58MHz *
3 * I
R2
Where FOUTX = Nominal rated frequency (4Hz, 290Hz or 1160Hz)
FOSC
I
I1
, I
I2
, I
I3
I
R
= Oscillator frequency (2MHz ...... 4MHz)
= Input currents for current inputs (16µA at rated)
= Reference current (typically 50µA)
I
V1
, I
V2
, I
V3
= Input currents for voltage inputs (14µA at rated)
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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