s-35199a01 Seiko Instruments Inc., s-35199a01 Datasheet - Page 35

• Manufacturer Part Number: s-35199a01
• Description: 3-wire Real-time Clock
• Manufacturer: Seiko Instruments Inc.

Clock pulse
of real-time
second data
"00h"
Power supply
Rev.1.0
24-bit binary
32.768 kHz Output Pin
Timing of Clock Output from F32K Pin
Up-Count Operation
The S-35199A01 outputs a 32.768 kHz clock pulse from the INT , F32K, and FOUT pins. However, do not output 32.768
kHz from these three pins simultaneously because stability of the crystal oscillator is affected.
When using the function to clock-correction or adjusting the oscillation frequency, measure the oscillation frequency under
the usage conditions. For example, when using 32.768 kHz clock pulse which is output from the FOUT pin, measure this IC
while the pulse is being output from the pin.
The 32.768 kHz clock pulse of the oscillation frequency is output from the F32K pin. The F32K pin has an Nch open-drain
output. When the CTRL pin is in “H”, the clock pulse is output, and when the CTRL pin is in “L” or open, the F32K pin is in
high impedance. To output 32.768 kHz from the F32K pin, set the CTRL pin to “H” when one sec or more has elapsed after
power-on.
The up counter is a 24-bit read-only binary counter. This counter starts counting from “000000h” from power-on and returns
to “000000h” at the next clock after it has reached “FFFFFFh”. A clock pulse is a pulse that is output when the second-data
in the real-time data is “00h”. Therefore, some delay is made in the period that a clock pulse is being output due to Write
timing and Write data. The registers are not initialized unless power-on again, so that users are able to grasp the elapsed
time from power-on up to 30 years. Figure 40 shows the example of timing chart of up counter’s operation.
up counter
CTRL pin
F32K pin
_00
OFF
60 seconds or more.
A clock pulse is
Write real-time
ON
second data:
40 s
20 seconds
000000h
ON
40 s
Figure 40 Timing Chart of 24-Bit Binary Up Counter
Figure 39 Timing of Clock Output from F32K Pin
000001h 000010h
60 s
60 seconds or less.
A clock pulse is
Write real-time
Seiko Instruments Inc.
second data:
50 seconds
20 s
10 s
FFFFFFh
60 s
3-WIRE REAL-TIME CLOCK
000000h
60 s
OFF
S-35199A01
000001h
OFF
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