s-35392a Seiko Instruments Inc., s-35392a Datasheet - Page 17

• Manufacturer Part Number: s-35392a
• Description: 2-wire Real-time Clock
• Manufacturer: Seiko Instruments Inc.

Rev.1.3
Power-on Detector and Register Status
The power-on detection circuit operates by power-on the S-35392A, as a result each register is cleared; each register is set
as follows.
“1” is set in the POC flag (B0 in the status register 1) to indicate that power has been applied. In this case, be sure to
initialize. The POC flag is set to “0” due to initialization. (Refer to “ Register Status After Initialization”.)
For the regular operation of power-on detection circuit, as seen in Figure 18, the period to power-up the S-35392A is that
the voltage reaches 1.3 V within 10 ms after setting the IC’s power supply voltage at 0 V. When the POC flag (B0 in the
status register) is not in “1”, in this case, power-on the S-35392A once again.
Do not transmit data immediately after power-on at least 0.5 sec because the power-on detection circuit is operating.
Real-time data register :
Status register 1 :
Status register 2 :
INT1 register :
INT2 register :
Clock correction register :
Free register :
_00
*1. 0 V indicates that there are no potential differences between the VDD
pin and VSS pin of the S-35392A.
Figure 18 How to Raise the Power Supply Voltage
00 (Y), 01 (M), 01 (D), 0 (day of the week), 00 (H), 00 (M), 00 (S)
“01h”
“01h”
“80h”
“00h”
“00h”
“00h”
Seiko Instruments Inc.
Within 10 ms
1.3 V
0 V
2-WIRE REAL-TIME CLOCK
*1
S-35392A
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