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RX-8035SA (I2C-Bus Real Time Clock Module)
- Built in 32.768 kHz crystal unit
Frequency adjusted for high accuracy.(±5x10-6/Ta=+25°C)
- Interface Type
I2C-Bus Interface(400kHz)
- Operating voltage range
2.4V to 5.5V
- Wide voltage for Timekeeping
1.0V to 5.5V
- Low backup current
350nA(SA) 400nA(LC)/ 3V(Typ.)
- Event detection and Time stamp
One-shot full timestamp and interrupt.
- Dual event detection ports
Each terminal has a de-bounce circuit.
- Auto power switching functions
It switches VDD and VBAT, automatically
- Dual Alarm, Periodic interruption
- Epson prepared Linux driver for development
- https://www5.epsondevice.com/en/information/support/linux_rtc/
The registered trademark Linux® is used pursuant to a sublicense from LMI(Linux Mark Institute)
Application Manual
(ETM35E-11) (1.3MB)
Design Support Data Download
Block diagram
Overview
- The event detection and Timestamp function
- Dual event detection terminals.
- Selectable de-bounce period 35ms or 2s.
- Available event detection interrupt output.
- Power switching functions.
- An external diode is unnecessary to have a reverse current prevention switch built-in in
the VBAT side to connect a primary cell to. - When VDD is less than 2.4V, an internal source is switched to VBAT, and /RES is Low level.
When VDD voltage rises to higher than 2.52V, an internal source is switched to VDD, and /RES is released with 105ms delay. - Note: When the supply from VBAT, SCL and SDA are disabled.
- An external diode is unnecessary to have a reverse current prevention switch built-in in
- Alarm, Periodic interrupt, 32.768kHz clock output.
- Available monthly-alarm and weekly-alarm.
- Interrupt period are selectable from 2Hz to Monthly.
- CLKOUT outputs 32.768kHz clock powered by VDD.
Specifications (characteristics) *Refer to application manual for details.
Recommend Operating Conditions
Item | Symbol | Conditions | Min. | Typ. | Max. | Unit |
---|---|---|---|---|---|---|
Operating voltage | VACCESS | VDD | 2.4 | 3.0 | 5.5 | V |
Time keeping voltage | VCLK | VBAT | 1.0 | 3.0 | 5.5 | V |
Operating temperature | TOPR | - | -40 | +25 | +85 | °C |
Storage temperature | TSTG | - | -55 | - | +125 | °C |
Frequency characteristics
Item | Symbol | Conditions | Rating | Unit |
---|---|---|---|---|
Frequency tolerance | Δ f/f | Ta=+25°C VBAT=3.0V |
B: 5±23 *1 AA: 5±5 *2 AC: 0±5 *2 |
×10-6 |
Oscillation start-up time | tSTA | Ta=+25°C VDD=3.0V |
1 Max. | s |
Frequency/voltage characteristics | f/V | Ta = +25°C VDD=2.4V to 5.5V |
±1 Max. | ×10-6 |
*1 Equivalent to ±1 minute of monthly deviation (excluding offset.)
*2 Equivalent to ±13 seconds of monthly deviation (excluding offset.)
Current consumption characteristics
Ta=-40°C to +85°C
Item | Symbol | Conditions | Min. | Typ. | Max. | Unit |
---|---|---|---|---|---|---|
Current Consumption | lBAT | RX-8035SA VBAT=3.0V, VDD=0.0V SCL=SDA=GND |
- | 350 | 1200 | nA |
RX-8035LC VBAT=3.0V, VDD=0.0V SCL=SDA=GND |
400 | |||||
IDD | VDD=3.0V SCL=SDA=GND CLKOUT=open | - | 1.40 | 2.50 | µA |
Power supply detection voltage
Ta=-40°C to +85°C
Item | Symbol | Condition | Min. | Typ. | Max. | Unit |
---|---|---|---|---|---|---|
VBAT detect voltage | VLOW | - | 1.10 | 1.25 | 1.40 | V |
Power switching voltage (VDD to VBAT) |
VD2B | +25°C | 2.328 | 2.40 | 2.472 | V |
Pin function
Signal Name | Input/Output | Functions |
---|---|---|
SCL | Input | I2C serial clock. |
SDA | In/Out | I2C data in/out. |
VDD | - | Main power supply. |
VBAT | - | Power supply for backup. |
Vout | Output | Switched power out.(maximum output current 20mA) |
/ RES | Output | VDD voltage state. |
GND | - | Ground |
EVIN1 | Input | Event detection input 1 |
EVIN2 | Input | Event detection input 2 |
/ INTA | Output | Interrupt out A. |
/ INTB | Output | Interrupt out B. |
CLKOUT | Output | 32.768kHz output. (CMOS. Can not inhibit.) |
N.C. | - | Do not connect. |
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).