# X252012MMB4SI-24

**Yangxing Tech** · Crystals · SMD2520-4P

X252012MMB4SI-24 from Yangxing Tech, 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 1 of the 12 MHz fundamental AT-cut crystal, 10 pF load capacitance, 150 Ω max ESR. |
| 2 | GND | power_in | Ground pad shown as GND in the crystal connection drawing, not connected to the crystal terminals. |
| 3 | XTAL2 | passive | Crystal terminal 2 of the 12 MHz fundamental AT-cut crystal, 10 pF load capacitance, 150 Ω max ESR. |
| 4 | GND | power_in | Ground pad shown as GND in the crystal connection drawing, not connected to the crystal terminals. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Yangxing Tech |
| 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 |
|---|---|---|---|---|---|---|---|
| Frequency tolerance at 25℃ | f_tol | -10 |  | 10 | x10-6 | at 25℃ | 3 |
| Stability over temperature | f_tem | -20 |  | 20 | x10-6 |  | 3 |
| Frequency aging | f_age | -3 |  | 3 | x10-6/year |  | 3 |
| Equivalent Series Resistance | ESR |  |  | 150 | Ω |  | 3 |
| Shunt capacitance | C0 |  |  | 2 | pF |  | 3 |
| Operating temperature | T_use | -40 |  | 85 | ºC |  | 3 |
| Storage temperature | T_stg | -55 |  | 125 | ºC |  | 3 |
| Nominal frequency | f_nom |  | 12 |  | MHz |  | 3 |
| Load capacitance | CL |  | 10 |  | pF |  | 3 |
| Level of drive | DL |  | 100 |  | µW |  | 3 |

## CAD (KiCad official)

- Symbol: `X252012MMB4SI-24`
- Footprint: `Crystal:Crystal_SMD_2520-4Pin_2.5x2.0mm`
- 3D model: SMD2520-4P (KiCad packages3D, STEP)
- 3D model files: `x252012mmb4si-24-etched.step` / `x252012mmb4si-24-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `x252012mmb4si-24.step` / `x252012mmb4si-24.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Yangxing Tech datasheet](docs/x252012mmb4si-24-datasheet.pdf) (5 pp, sha256 `3f37aae9426f44cc`, retrieved 2026-10-21, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+vision), consensus `claude-opus-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/x252012mmb4si-24-datasheet.pdf)