DS1302Z from JSMSEMI, in a SOP-8. 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	VCC2	power_in	Primary power supply pin in a dual-supply configuration. When VCC2 is more than 0.2 V above VCC1 the DS1302 is powered from VCC2; otherwise it is powered from VCC1. Recommended operating range 2.0 V to 5.5 V.
2	X1	input	Connection for a standard 32.768 kHz quartz crystal (with matching 6 pF load capacitance). May alternatively be driven by an external 32.768 kHz oscillator signal, in which case X2 is left floating.
3	X2	output	Second connection for the 32.768 kHz quartz crystal (internal oscillator output). Leave floating if the DS1302 is driven by an external oscillator source on X1.
4	GND	power_in	Device ground / 0 V reference.
5	CE	input	Chip enable input. Must be driven high to initiate any read or write transaction on the 3-wire serial interface; driving CE low terminates the transfer and places I/O in high-impedance. Internally pulled down to GND through a typical 40 kΩ resistor.
6	I/O	bidirectional	Bidirectional data pin of the 3-wire serial interface (push-pull output). Carries command/address and data bytes to/from the DS1302. Internally pulled down to GND through a typical 40 kΩ resistor.
7	SCLK	input	Serial clock input used to synchronize data movement on the 3-wire interface. Internally pulled down to GND through a typical 40 kΩ resistor. Maximum clock rate is 2.0 MHz at VCC = 5.0 V (0.5 MHz at VCC = 2.0 V).
8	VCC1	power_in	Backup power supply pin, typically connected to a coin cell, super-cap, or (in trickle-charged systems) the rechargeable energy source. Supplies the DS1302 when VCC2 falls below VCC1, preserving time and date. UL requires that reverse charging current into a lithium primary cell be prevented.

Key specifications

Parameter	Value
Manufacturer	JSMSEMI
Package	SOP-8
Category	RTC
Pins	8

Ordering variants

Same part, different packaging or reel option.

DS1302Z
DS1302ZN
DS1302N

CAD (KiCad official)

Symbol: DS1302Z
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOP-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`ds1302z.step`	122 KB	You want the bare part, or you mark your own boards.
`ds1302z-etched.step`	1.8 MB	You want the part with `DS1302Z` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 431 faces against 147 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: JSMSEMI datasheet (14 pp, sha256 a589fafaf79fdd18, 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