RX-4571SA (Low Backup Voltage Serial-Interface Real Time Clock Module)

  • Built in frequency adjusted 32.768kHz crystal unit.
  • Interface Type
    3-wire serial interface
  • Operating voltage range
    1.6V to 5.5V
  • The wide voltage for time keeping
    1.0V to 5.5V / Ta=+25°C
  • Low backup current
    0.32µA(Typ.) / 3V
  • 32.768kHz frequency output function
    C-MOS output With OE pin
  • Real-time clock function
    Clock/calendar function, auto leap year correction function,
    Alarm and Timer interrupt function, etc.

Complies with EU RoHS directive.


Block diagram

Block diagram


  • 32.768kHz frequency output function
    • FOUT pin output(C-MOS output), CL=30pF
  • Timer function
    • Timer function which can be set up between 1/4096second and 4095minutes.
  • Alarm function
    • Alarm function can be set to any combination of day, day of week, hour, or minute.

Specifications *Refer to application manual for details.

Recommend Operating Conditions

Item Symbol Condition Min. Typ. Max. Unit
Power voltage VDD - 1.6 3.0 5.5 V
Clock voltage VCLK Ta=+25°C 1.0 3.0 5.5 V
Ta=-40 to +85°C 1.1 3.0 5.5 V
Operating temperature TOPR - -40 +25 +85 °C

Frequency characteristics

Item Symbol Condition Rating Unit
Frequency tolerance Δ f/f Ta=+25°C
5±23 * ×10-6
Oscillation start-up time tSTA Ta=+25°C
1Max. s

* Please ask for tighter tolerance. (Equivalent to ±1 minute of monthly deviation)

Current consumption characteristics

*Ta=-40°C to +85°C

Item Symbol Conditions Min. Typ. Max. Unit
Current consumption lBK CE=GND

FOUT;output OFF(Hi-z)
VDD=5V - 0.40 1.00 µA
VDD=3V - 0.32 0.95
l32k CE=GND

FOUT; 32.768kHz output ON
VDD=5V - 8.0 14.0 µA
VDD=3V - 5.0 8.5


Pin function

Signal Name Input/Output Function
CE Input The chip enabled input pin 0. ( It has a built -in pull-down resistance )
CLK Input The shift clock input pin for serial data transfer.
DIO Bi-directional The data input / output pin for serial data transfer.
FOUT Output 32.768kHz clock output pin with the output control function. (C-MOS)
FOE pin control the condition of FOUT with FSEL1-bit, FSEL0-bit, etc.
FOE Input
/ IRQ Output Interrupt output (N-ch open drain)
VDD - Connected to a positive power supply.
GND - Connected to a ground.

Terminal connection / External dimensions

Terminal connection External dimensions

(Unit: mm)

The metal case inside of the molding compound may be exposed on the top or bottom of this product.
This purely cosmetic and does not have any effect on quality, reliability or electrical specs.

Footprint (Recommended)


(Unit: mm)

To maintain stable operation, provide a 0.1uF by-pass capacitor
at a location as near as possible to the power source terminal of the crystal product (between Vcc - GND).

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