# ECS-120-8-36-CKM-TR

**ECS** · Crystals · SMD2520-4P

ECS-120-8-36-CKM-TR from ECS, 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 | In/Out | passive | Crystal terminal (In/Out); the crystal is symmetrical and pads 1 and 3 are interchangeable. |
| 2 | Gnd | power_in | Ground pad (Gnd) for the crystal package; the datasheet gives no electrical limits for this pad. |
| 3 | Out/In | passive | Crystal terminal (Out/In); the crystal is symmetrical and pads 1 and 3 are interchangeable. |
| 4 | Gnd | power_in | Ground pad (Gnd) for the crystal package; the datasheet gives no electrical limits for this pad. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | ECS |
| 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 (P/N code C) |  | -10 |  | 10 | ppm | @ +25°C; P/N tolerance letter C = ±10 ppm (family default printed as ±50 ppm) | 1 |
| Frequency stability (P/N code K) |  | -10 |  | 10 | ppm | -20 ~ +70°C; P/N stability letter K = ±10 ppm (family default printed as ±50 ppm) | 1 |
| Aging (first year) |  | -5 |  | 5 | ppm | @ +25°C ±3°C | 1 |
| Operating temperature | Topr | -20 |  | 70 | °C | P/N temperature code M = -20 ~ +70°C | 1 |
| Storage temperature | Tstg | -55 |  | 125 | °C |  | 1 |
| ESR |  |  |  | 150 | Ω | 12.000 ~ 15.999 MHz | 1 |
| Frequency |  |  | 12 |  | MHz | P/N frequency code 120 = 12.000 MHz | 1 |
| Load capacitance |  |  | 8 |  | pF | Specify in P/N; P/N code 8 = 8 pF | 1 |
| Shunt capacitance | Co |  | 5 |  | pF |  | 1 |
| Drive level | DL |  | 100 |  | μW |  | 1 |
| Peak solder temperature |  |  |  | 260 | °C | 10 sec max; 2 cycles max; MSL 1 | 2 |

## CAD (KiCad official)

- Symbol: `ECS-120-8-36-CKM-TR`
- Footprint: `Crystal:Crystal_SMD_2520-4Pin_2.5x2.0mm`
- 3D model: SMD2520-4P (KiCad packages3D, STEP)
- 3D model files: `ecs-120-8-36-ckm-tr-etched.step` / `ecs-120-8-36-ckm-tr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ecs-120-8-36-ckm-tr.step` / `ecs-120-8-36-ckm-tr.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [ECS datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8589814631234904064) (2 pp, sha256 `dfda265f7b2eeae3`, retrieved 2026-10-15, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-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/ecs-120-8-36-ckm-tr-datasheet.pdf)