RX8804CE
Page - 1
ETM59E-05
I
2
C-Bus Interface Real-time Clock Module
RX8804
CE
1. Overview
This module is an I
2
C-Bus interface-compliant real-time clock which includes a 32.768 kHz DTCXO
.
In addition to providing a calendar (year, month, date, day, hour, minute, second) function and a clock counter
function, this module provides an abundance of other functions including an alarm function, wakeup timer function,
time update interrupt function, 32.768 kHz output function, Time stamp function with EVIN-pin trigger,
and. Programmable output function to SOUT-pin of interrupt Flags or self monitoring Flags.
The devices in this module are fabricated via a CMOS process for low current consumption, which enables long-
term battery back-up.
2. Block Diagram
Figure 1 Block Diagram
•
Built-in 32.768 kHz DTCXO
•
Interface Type
: I
2
C-Bus (Up to 400 kHz)
•
Low current consumption at backup
: 350 nA / 3.0 V Typ.
•
Wide time-keeping voltage range
: 1.5 V to 5.5 V
•
Wide interface voltage range
: 1.6 V to 5.5 V
•
SOUT can output self monitoring status, voltage down etc.
: SOUT can output programmed H / L level also.
•
Time stamp function of Seconds from Year
: One time recorded by trigger of EVIN.
•
EVIN is equipped for time stamp trigger
: It has connectable pull up resistor
•
Alarm interrupt function
: Combination of Day, Date, Hour, Minute, and AE bit
•
Wakeup timer interrupt function
: Auto repeated 244.14 µs to 32 years
•
Time update interrupt function
: Every second or every minute
•
Temperature compensated 32.768 kHz or other output
: Available output enable control
•
Auto correction of leap years
: Writing of "60 seconds" is available for Leap Second
adjustment
The I
2
C-Bus is a trademark of NXP Semiconductors
INTERRUPTS
CONTROLLER
ALARM REGISTER
/INT
BUS
INTERFACE
CIRCUIT
( 32.768 kHz )
CONTROL
REGISTER
DIVIDER
CLOCK
POWER
CONTROLLER
and
SDA
V
DD
SCL
CALENDR
TIMER REGISTER
DTCXO
CONTROLLER
FOUT
FOUT
FOE
CONTROLLER
SOUT
SOUT
CONTROLLER
EVENT DETECTION
EVIN
CAPTURE
BUFFER
VDD
SYSTEM
CONTROLLER