# ECS-120-18-5PX-TR

**ECS INTERNATIONAL INC** · Global Sourcing Parts · HC-49S-SMD

ECS-120-18-5PX-TR from ECS INTERNATIONAL INC, in a HC-49S-SMD. 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 (connecting pin); the crystal is symmetrical so pins 1 and 2 are interchangeable. |
| 2 | XTAL2 | passive | Crystal terminal 2 (connecting pin); the crystal is symmetrical so pins 1 and 2 are interchangeable. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | ECS INTERNATIONAL INC |
| Package | HC-49S-SMD |
| Category | Global Sourcing Parts |
| Pins | 2 |

## 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 @ +25°C |  | -30 |  | 30 | ppm | @ +25°C; Standard (no tolerance letter in P/N) | 1 |
| Frequency Stability (Standard) |  | -50 |  | 50 | ppm | -10 ~ +70°C; Standard (no stability letter in P/N) | 1 |
| Aging (First Year) |  | -5 |  | 5 | ppm | @ +25°C ±3°C, first year | 1 |
| Equivalent Series Resistance (ESR) |  |  |  | 50 | Ω | Frequency 9.000 ~ 12.999 MHz, Fundamental mode | 1 |
| Shunt Capacitance | Co |  |  | 7 | pF |  | 1 |
| Drive Level | DL |  |  | 500 | μW |  | 1 |
| Operating Temperature | Topr | -10 |  | 70 | °C |  | 1 |
| Storage Temperature | Tstg | -55 |  | 125 | °C |  | 1 |
| Nominal Frequency |  |  | 12 |  | MHz | P/N code 120 = 12.000 MHz per part-numbering guide | 1 |
| Peak Solder Temperature |  |  |  | 260 | °C | Max 10 sec; 2 cycles max | 2 |

## Materials and finish

As the datasheet states them (page.json `metadata.appearance`; the 3D model's colours follow it).

| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| contacts |  | tin | MSL 1, Lead Finish Sn/Cu Matte POCKET TAPE DIMENSIONS (mm) | 2 |

## CAD (KiCad official)

- Symbol: `ECS-120-18-5PX-TR`
- Footprint: `Crystal:Crystal_SMD_HC49-SD`
- 3D model: HC-49S-SMD (KiCad packages3D, STEP)
- 3D model files: `ecs-120-18-5px-tr-etched.step` / `ecs-120-18-5px-tr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ecs-120-18-5px-tr.step` / `ecs-120-18-5px-tr.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [ECS INTERNATIONAL INC datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590909282017615872) (2 pp, sha256 `e6475dc08877362d`, retrieved 2026-10-19, tier: lcsc)
- **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/ecs-120-18-5px-tr-datasheet.pdf)