S-35390A Seiko Instruments, S-35390A Datasheet - Page 16

• Manufacturer Part Number: S-35390A
• Description: 2-Wire Real Time Clock
• Manufacturer: Seiko Instruments

16
2-WIRE REAL-TIME CLOCK
S-35390A
Initialization at Power-on and Power-on Detector
When power is applied to this IC, status register_1 is set to “80h” (bit 7 (POC flag) of status register_1 is set
to “1”) by the power-on detector and a 1 Hz clock is output from the
adjust the oscillation frequency. In normal use, the IC must be initialized at power-on. Initialization is
performed by writing “1” to bit 0 (RESET flag) of status register_1.
Register State After Initialization
Also, the IC must be initialized when the POC flag is set to “1”. After initialization, the POC flag is set to “0”.
For normal operation of the power-on detector, first hold the IC power supply voltage at 0 V and then
increase it.
The state of each register after initialization is as follows.
Real-time data register:
Status register_1:
Status register_2:
INT1 register_1:
INT1 register_2:
Clock adjustment register: “00h”
Free register:
00 (year), 01 (month), 01 (day), 0 (day of week), 00 (hour), 00 (minute),
00 (second)
“0 0 0 0 B3 B2 B1 0 b” (The B3, B2, and B1 data of status register_1 after
initialization are set in B3, B2, and B1.)
“00h”
“00h”
“00h”
“00h”
Seiko Instruments Inc.
INT pin. This function is provided to
1
Rev.1.2
_00