RX4111CE
Real-time clock module by Epson
The RX4111CE is a real-time clock module from Epson with a built-in 32.768 kHz crystal — no separate watch crystal on the board, no load capacitance and layout risk. Interface SPI, package CE · 3.2 × 2.5 × 1.0 mm, standby current 100 nA typ. · 450 nA max., accuracy ±11.5 ppm at +25 °C (not compensated), operating range −40 … +105 °C. SPI counterpart to the RX8111CE (4-wire), with V_IO pin.
What the RX4111CE can do
The tolerance figure applies at +25 °C. Over temperature the built-in crystal follows the usual parabola.
Detects the loss of the main supply and switches to the backup source on its own — compared with a diode-OR arrangement the MOS switch saves leakage current and voltage drop.
Events are recorded with their time inside the device, without the MCU having to wake up for it.
A separate level for the interface: the device runs on 3 V but talks to a 1.8 V MCU without a level shifter.
Reports an oscillation stop instead of quietly delivering the wrong time.
Alternatives in the Epson programme
If the RX4111CE is not quite the right fit — these types come closest:
RX8111CE
Same series, I²C instead of SPI. Otherwise largely identical figures.
RX4901CE
If the clock has to hold over temperature as well: DTCXO, ±3.0 ppm over −40 … +85 °C (DTCXO).
All 40 families with filters for interface, package, standby current and temperature: real-time clock finder.
Frequently asked questions about the RX4111CE
How accurate is the RX4111CE?
±11.5 ppm at +25 °C (not compensated). This figure applies at +25 degrees Celsius. Over temperature the built-in crystal follows the usual parabola — if the clock has to hold when hot and cold as well, a DTCXO type is the right choice.
How much current does the RX4111CE draw in backup?
100 nA typ. · 450 nA max.. With a 225 mAh coin cell that is enough for many years of pure timekeeping on paper; the self-discharge of the cell usually becomes the limiting factor.
Which interface does the RX4111CE use?
SPI. Package: CE · 3.2 × 2.5 × 1.0 mm.
Where can I buy the RX4111CE in Europe?
Timing Devices Europe stocks the Epson RTC programme in its own warehouse in Ladenburg near Heidelberg, Germany — physically on site, not at the manufacturer. Samples, series demand and second-source assessment in one go, answered the same working day.
Enquire about the RX4111CE.
We stock the Epson RTC programme in our own warehouse in Ladenburg near Heidelberg, Germany. Tell us tolerance grade, packing, quantity and date — answered the same working day.