Time stamp function and Low current consumption

  • - Built in frequency adjusted
     32.768 kHz crystal unit
  • - Interface Type
    I2C-Bus interface
     SPI-Bus interface Product : RX4111CE  Link
  • - Low backup current
    100 nA Typ. / 3 V
  • - Operating Temperature
    -40 ℃ to +105 ℃
  • - Auto power switching function
    Automatically switches to backup power supply by
    monitoring the VDD voltage
  • - Time stamp function
    8 times stamped from year to 1/256 seconds.
  • - Interrupt output
    Wake up every minute or every second
  • - Alarm interruption in Day, date,
      hour, minute, second
  • - Auto repeat wakeup timer interruption
  • - Self-monitoring interruption
    Crystal oscillation stop.
    VBAT low, VDD low.
  • · Links to convenient tools  Click here
  • · Links to Driver and Video contents  Click here

Complies with EU RoHS directive.

Complies with EU RoHS directive.


Block diagram

Block diagram


  • Interface Type
    • I2C-Bus interface Fast-Mode 400 kHz
  • Auto power switching function
    • The VDD voltage is monitored and it switches to the backup power supply by the automatic operation
    • Backup power supply switching voltage 1.2 V Min.
  • Clock output function
    • Output frequency is selectable from 32.768 kHz, 1024 Hz,1 Hz
  • Wakeup timer function
    • Selectable from 244 micro second to 32 years (24 bit 1 ch.)
    • Timer source clock selectable from 1/60 Hz, 1 Hz, 64 Hz, 4096 Hz
    • Auto release after interrupt output from /INT pin at timer completes
    • This operation is auto repeat with a selected cycle, it can be used like a watchdog timer
  • Time stamp function
    • 8 times stamped from year to 1/256 seconds
    • The time-stamp trigger inputs from EVIN pin, self-monitoring and I2C software command
    • EVIN pin has function of chattering-cancel
  • Alarm function
    • It is possible program from year to second
  • Self-monitoring interruption
    • Crystal oscillation stop. VBAT low, VDD low

Specifications (characteristics)

Refer to application manual for details

name name

Pin function

Signal Name I / O Function
EVIN input External event input pin (Pull up/down and polarity are selectable by software)
SCL input Serial clock input pin
SDA Input / Output Data input and output pin
FOUT Output Frequency output (CMOS)
(frequency selection: 32.768 kHz / 1024 Hz / 1 Hz)
/INT Output Interrupts output by Alarm and Timer events (N-ch. open drain)
VDD - Power-supply pin.
It can input the voltage unlike VIO
VIO - Interface power supply pin.
Input to supply the voltage same as a host
VOUT - Internal voltage output pin. Connect smoothing capacitor of 1.0 µF surely
VBAT - This is a power supply pin for backup battery
Connect a EDLC, secondary battery, a primary battery
In the backup voltage range, supplied to IC, from this pin
GND - Ground pin

Terminal connection/External dimensions

Terminal connection External dimensions

(Unit: mm)

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)

Video contents: How to use Real Time Clock Module evaluation board(RX8900CE, RX8804CE)

Video contents: RX8111CE: Battery backup switchover function

Video contents: RX8111CE: Time stamp function

Video contents: RX8111CE: Wake up timer function

Video contents: RX4111CE: Battery backup switchover function

Real Time Clock: RX8900CE / RX8804CE Evaluation Tools

Linux® Driver for Real Time Clock Module

The registered trademark Linux® is used pursuant to a sublicense from LMI (Linux Mark Institute)

Product Brief/White Paper/Technical Note

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