RX8025T-UB from Seiko Epson, in a SOP-14-208mil. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	T1/CE	input	Manufacturer test pin (T1, also labeled CE). Must be left unconnected externally.
2	SCL	input	I2C serial clock input. Fmax = 400 kHz (Fast-mode). Requires external pull-up to VDD; no internal ESD diode to VDD, allowing level-shifted operation.
3	FOUT	output	CMOS 32.768 kHz clock output. Enabled when FOE = H (outputs 32.768 kHz); when disabled the pin is Hi-Z. Drive per DC characteristics (e.g. VOH >= 2.9 V at IOH = -100 uA, VDD = 3 V).
4	NC	unconnected	Not connected to the internal IC. Leave open or tie to GND or VDD.
5	TEST	input	Manufacturer test pin. Must be left unconnected externally.
6	VDD	power_in	Positive supply pin. Interface operating range 1.6-5.5 V (typ. 3.0 V); time-keeping down to 1.2 V. Bypass with at least 0.1 uF between VDD and GND.
7	FOE	input	FOUT output enable. Level 'H' enables the 32.768 kHz FOUT output; level 'L' places FOUT in Hi-Z. VIH >= 0.8VDD, VIL <= 0.2VDD.
8	NC	unconnected	Not connected to the internal IC. Leave open or tie to GND or VDD.
9	NC	unconnected	Not connected to the internal IC. Leave open or tie to GND or VDD.
10	/INT	output	Open-drain interrupt output for alarm, fixed-cycle timer, and time-update events. Asserts low when an interrupt fires; requires external pull-up. VOL <= GND+0.25 V at IOL = 1 mA, VDD = 5 V.
11	GND	power_in	Module ground reference (0 V).
12	T2/VPP	passive	Manufacturer test pin (T2, also labeled VPP). Must be left unconnected externally.
13	SDA	bidirectional	I2C serial data (address/data/ACK). N-channel open-drain output; requires external pull-up sized for the bus capacitance. No internal VDD diode, supports level-shifted buses.
14	NC	unconnected	Not connected to the internal IC. Leave open or tie to GND or VDD.

Key specifications

Parameter	Value
Manufacturer	Seiko Epson
Package	SOP-14-208mil
Category	RTC
Pins	14

Ordering variants

Same part, different packaging or reel option.

RX8025T-UB

CAD (KiCad official)

Symbol: RX8025T-UB
Footprint: Package_SO:SOIC-14_3.9x8.7mm_P1.27mm
3D model: SOP-14-208mil (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`rx8025t-ub.step`	195 KB	You want the bare part, or you mark your own boards.
`rx8025t-ub-etched.step`	2.6 MB	You want the part with `RX8025T-UB` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 634 faces against 237 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Seiko Epson datasheet (33 pp, sha256 e061d6f8feb4ec7e, retrieved 2026-08-17, tier: lcsc)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF