# Q25000C018

**ECEC(ZheJiang E ast Crystal Elec)** · Crystals · SMD2520-4P

Q25000C018 from ECEC(ZheJiang E ast Crystal Elec), in a SMD2520-4P. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | XTAL1 | passive | Crystal terminal connected to the quartz element (marked with the chamfered pad corner), for the 25.000000 MHz fundamental-mode crystal with 10 pF load capacitance. |
| 2 | CASE_GND | passive | Pad connected to the metal cover (lid) and not to the quartz element, normally grounded or left unconnected. |
| 3 | XTAL2 | passive | Crystal terminal connected to the quartz element, the second oscillator connection for the 25.000000 MHz crystal. |
| 4 | CASE_GND | passive | Pad connected to the metal cover (lid) and not to the quartz element, normally grounded or left unconnected. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | ECEC(ZheJiang E ast Crystal Elec) |
| Package | SMD2520-4P |
| Category | Crystals, Oscillators, Resonators |
| Pins | 4 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Equivalent Resistance | Rr |  |  | 60 | Ω |  | 3 |
| Shunt Capacitance | C0 |  |  | 2 | pF |  | 3 |
| Insulation Resistance |  | 500 |  |  | MΩ | at DC 100V | 3 |
| Frequency Tolerance |  | -10 |  | 10 | ppm |  | 3 |
| Temperature drift (TC) |  | -10 |  | 10 | ppm |  | 3 |
| Aging |  | -2 |  | 2 | ppm | First Year | 3 |
| Operating Temperature |  | -20 |  | 70 | ℃ |  | 3 |
| Storage Temperature Range |  | -55 |  | 125 | ℃ |  | 3 |
| Nominal Frequency | FL |  | 25 |  | MHz |  | 3 |
| Drive Level | DL |  | 100 |  | uW |  | 3 |

## CAD (KiCad official)

- Symbol: `Q25000C018`
- Footprint: `Crystal:Crystal_SMD_2520-4Pin_2.5x2.0mm`
- 3D model: SMD2520-4P (KiCad packages3D, STEP)
- 3D model files: `q25000c018-etched.step` / `q25000c018-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `q25000c018.step` / `q25000c018.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [ECEC(ZheJiang E ast Crystal Elec) datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8756858398258274304) (10 pp, sha256 `cfd5efdc58b96a52`, retrieved 2026-10-21, 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](docs/q25000c018-datasheet.pdf)