RTC - 4543 SA/SB
Page - 1
MQ - 252 - 03
32-kHz Output Serial RTC Module
RTC - 4543 SA/SB
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Built-in crystal permits operation without requiring adjustment
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Built-in time counters (seconds, minutes, hours) and calendar counters (days, days of the week
months, years)
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Operating voltage range: 2.5 V to 5.5 V
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Supply voltage detection voltage: 1.7
±
0.3 V
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Low current consumption: 1.0
µ
A/2.0 V (Max.)
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Automatic processing for leap years
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Output selectable between 32.768 kHz/1 Hz
1. Overview
This module is a real-time clock with a serial interface and a built-in crystal oscillator. This module
is also equipped with clock and calendar circuits, an automatic leap year compensation function,
and a supply voltage detection function.
In addition, this module has a 32.768 kHz/1 Hz selectable output function for hardware control that
is independent of the RTC circuit.
This module is available in a compact SOP 14-pin package (RTC-4543SA) and a thin SOP 18-pin
package (RTC-4543SB).
2. Block diagram
OSC
FOUT
I / O
CONTROLLER
SHIFT REGISTER
C
L
K
DATA
CE
WR
32.768 kHz
DIVIDER
OUTPUT
CONTROLLER
FOE
CONTROL
CIRCUIT
FSEL
VOLTAGE
DETECT
CLOCK AND CALENDAR