s-35190a Seiko Instruments Inc., s-35190a Datasheet - Page 37

• Manufacturer Part Number: s-35190a
• Description: 3-wire Real-time Clock
• Manufacturer: Seiko Instruments Inc.

Rev.2.4
2. Measurement of oscillation frequency
When the S-35190A is turned on, the internal power-on detector operates and a signal of 1 Hz is output from the INT pin
to select the crystal oscillator and optimize the C
counter following the circuit configuration shown in Figure 46 .
If 1 Hz signal is not output, the power-on detector does not operate normally. Turn off the power and then turn it on
again. For how to apply power, refer to “ Power-on Detector and Register Status” .
Caution
Remark If the error range is ± 1 ppm in relation to 1 Hz, the time is shifted by approximately 2.6 seconds per month
_00
10 kΩ
Open
(calculated using the following expression).
10
1. Use a high-accuracy frequency counter of 7 digits or more.
2. Measure the oscillation frequency under the usage conditions.
3. Since the 1 Hz signal continues to be output, initialization must be executed during normal
–6
(1 ppm) × 60 seconds × 60 minutes × 24 hours × 30 days = 2.592 seconds
operation.
10 kΩ
Figure 46 Configuration of Oscillation Frequency Measurement Circuit
SIO
SCK
CS
S-35190A
Seiko Instruments Inc.
g
value. Turn the power on and measure the signal with a frequency
XOUT
VDD
VSS
XIN
INT
C
3-WIRE REAL-TIME CLOCK
g
10 kΩ
Frequency
counter
S-35190A
37