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RX-8731LC (Built-in EEPROM and Unique ID-ROM I2C-Bus Interface Real Time Clock Module)
- Built in frequency adjusted 32.768kHz crystal unit.
- Interface Type
I2C-Bus interface (400 kHz)
- Operating voltage range
1.7V to 5.5V
- •Wide voltage for timekeeping
1.3V to 5.5V
- Low backup current
0.35µA / 3V(Typ.)
- 32.768kHz frequency output function
C-MOS output With Control Pin
- The various functions include full calendar, alarm, timer
Block diagram
Overview
- Built in EEPROM and ID-ROM
- Built in 10Byte ( 80bit) EEPROM
- Built in 6Byte ( 48bit ) ID-ROM
- Programmable I/O ports
- 4Programmable I/O ports
- Interface Type
- I2C-Bus high-speed bus specifications. (400kHz)
- 32.768kHz frequency output function
- FOUT pin output (C-MOS output), CL=30pF
- FOE pin enables output on/off control.
- Output frequency is selectable.
< 32.768kHz, 1024 Hz, 1 Hz >
- The various interrupt function
- Alarm interrupt function
- Timer interrupt function
- Update interrupt function
Specifications *Refer to application manual for details.
Recommend Operating Conditions
Item | Symbol | Condition | Min. | Typ. | Max. | Unit |
---|---|---|---|---|---|---|
Power voltage | VDD | - | 1.7 | 3.0 | 5.5 | V |
Clock voltage | VCLK | - | 1.3 | 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 VDD=3.0V |
5±23 * | ×10-6 |
Oscillation start-up time | tSTA | Ta=+25°C VDD=1.6V |
1Max. | s |
Ta=-40°C to +85°C VDD=1.6V |
3Max. | s |
* Please ask for tighter tolerance. (Equivalent to ±1 minute of monthly deviation)
Current consumption characteristics
Item | Symbol | Conditions | Min. | Typ. | Max. | Unit | |
---|---|---|---|---|---|---|---|
Current Consumption |
lBK | fSCL=0 Hz / IRQ = OFF FOUT: output OFF(Hi-z) |
VDD=5V | - | 0.45 | 1.5 | µA |
VDD=3V | - | 0.35 | 1.4 | ||||
l32k | fSCL=0 Hz / IRQ = OFF FOUT:32.768kHz output CL=30pF |
VDD=5V | - | 8.0 | 16.0 | µA | |
VDD=3V | - | 5.0 | 10.0 |
Pin function
Signal Name | Input/Output | Function |
---|---|---|
SCL | Input | Serial Clock input pin. |
SDA | Bi-directional | Data input and output pin. |
A 0 | Input | Device address A0 input pin. |
FOUT | Output | FOUT pin is 32.768kHz clock output pin (C-MOS) that output control is possible. FOE pin control the frequency output from FOUT pin with FSEL1-bit and FSEL0-bit. |
FOE | Input | |
/ IRQ | Output | Interrupt output pin. (N-ch open drain) |
P00 P01 P02 P03 |
Bi-directional | Programmable I/O ports. |
VDD | - | Connected to a positive power supply. |
GND | - | Connected to a ground. |
Terminal connection / External dimensions
(Unit: mm)
Stop using the glue
Any glue must never use it after soldering LC-package to a circuit board.
This product has glass on the back side of a package.
When glue invasions between circuit board side and glass side, then glass cracks by thermal expansion of glue.
In this case a crystal oscillation stops.Consider glue abolition or glue do not touch to LC-package
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).