PT7C43390 Datasheet, PDF (24/38 Pages) Pericom Semiconductor Corporation – Real-time Clock Module

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PT7C43390/43390C
Real-time Clock Module
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*1. Pin output is set to "H" by disabling the output mode within 7.81 ms, because the signal of this procedure is maintained for
7.81 ms. Note that pin output is set to "L" by setting enable the output mode again.
Timing of Per-minute Edge Interrupt Output
d. Minute-periodical interrupt output 1
The minute-periodical interrupt 1 is the function to output the one-minute clock pulse (Duty 50%) from the INT2 pin, when the
first minute-carry processing is done, after selecting the output mode.
*1. Setting the output mode disable makes the pin output "H", while the output from the INT2 pin is in "L".
Note that pin output is set to "L" by setting enable the output mode again.
Timing of Minute-periodical Interrupt Output 1
10. Function to Clock Correction
The function to clock correction is to correct advance / delay of the clock due to the deviation of oscillation frequency, in order to
make a high precise clock. For correction, the RTC adjusts the clock pulse by using a certain part of the dividing circuit, not
adjusting the frequency of the crystal oscillator. Correction is performed once every 20 seconds (or 60 seconds). The minimum
resolution is approx. 3 ppm (
data,
refer to "15.2. How to calculate". When not using this function, be sure to set "00h".
Function to Clock Correction
2015-12-0001
PT0280-8 12/11/15
24