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RX8900CE
Real-time clock module by Epson

The RX8900CE 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 I²C, package CE · 3.2 × 2.5 × 1.0 mm, standby current 700 nA typ. · 1400 nA max., accuracy ±3.4 ppm over −40 … +85 °C (DTCXO), operating range −40 … +85 °C. The DTCXO classic. Note: backup switchover only from 2.5 V, compensation from 2.0 V.

I²CDTCXOPower switchCE 3.2 × 2.5 × 1.0
InterfaceI²C
PackageCE · 3.2 × 2.5 × 1.0 mm
Standby current700 nA typ. · 1400 nA max.
Accuracy±3.4 ppm over −40 … +85 °C (DTCXO)
Temperature range−40 … +85 °C
Supply2.5–5.5 V · timekeeping from 1.6 V
Tolerance gradesUA / UB
AvailabilityEx stock Ladenburg near Heidelberg

What the RX8900CE can do

DTCXO

Digitally temperature compensated — the stated accuracy holds across the whole temperature range, not only at +25 °C.

Power switch

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.

Order codes and datasheets

Every order code has its own printable datasheet with all recorded figures.

TDE itemEpson designation
91-0013RX8900CE UA
91-0014RX8900CE UB
91-0015RX8900CE UC
91-0201RX8900CE UA
91-0202RX8900CE UA
91-0203RX8900CE UA
91-0204RX8900CE UA
91-0205RX8900CE UA
91-0206RX8900CE UB/UC
91-0207RX8900CE UB/UC
91-0208RX8900CE UB/UC
91-0209RX8900CE UB/UC
91-0210RX8900CE UB/UC
91-0211RX8900CE UB/UC

There are 18 order codes for this family in the programme — you will find the rest through the datasheet search.

Alternatives in the Epson programme

If the RX8900CE is not quite the right fit — these types come closest:

All 40 families with filters for interface, package, standby current and temperature: real-time clock finder.

Frequently asked questions about the RX8900CE

How accurate is the RX8900CE?

±3.4 ppm over −40 … +85 °C (DTCXO). Because the device is digitally temperature compensated, that figure holds across the whole temperature range.

How much current does the RX8900CE draw in backup?

700 nA typ. · 1400 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 RX8900CE use?

I²C. Package: CE · 3.2 × 2.5 × 1.0 mm.

Where can I buy the RX8900CE 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.

Samples and series demand

Enquire about the RX8900CE.

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.

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