# HCM494000000ABJT

**CITIZEN** · Crystals · HC-49S-SMD

HCM494000000ABJT from CITIZEN, 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 | 1 | passive | Terminal 1 of a two-terminal crystal; either orientation. |
| 2 | 2 | passive | Terminal 2 of a two-terminal crystal; either orientation. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | CITIZEN |
| Package | HC-49S-SMD |
| Category | Crystals, Oscillators, Resonators |
| 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 range f0 | f0 | 3.5 |  | 50 | MHz | 3.5 MHz to 30.0 MHz fundamental; 30.0 MHz to 50.0 MHz 3rd overtone | 1 |
| Frequency tolerance at 25°C | Δf/f0 | -30 |  | 30 | ppm | at 25℃, suffix A (STD) | 1 |
| Frequency tolerance over operating temperature range | Δf/f0 | -50 |  | 50 | ppm | below 6.0 MHz, -10℃ to +60℃ | 1 |
| Aging (first year) | Δf/f | -5 |  | 5 | ppm | 25℃±3℃, first year | 1 |
| Insulation resistance | IR | 500 |  |  | MΩ | DC100V±15V | 1 |
| Shunt capacitance | C0 |  |  | 7 | pF |  | 1 |
| Level of drive | DL |  |  | 100 | μW |  | 1 |
| Operating temperature range | OPR | -40 |  | 85 | ℃ |  | 1 |
| Storage temperature range | STR | -55 |  | 125 | ℃ |  | 1 |
| Load capacitance (fundamental) | CL | 10 |  |  | pF | Fundamental mode, upper limit ∞ | 1 |
| Nominal frequency | f0 |  | 4 |  | MHz | MPN frequency digits 4000000 (Hz) | 2 |
| Load capacitance (ordering suffix J) | CL |  | 18 |  | pF | ordering suffix J | 2 |

## CAD (KiCad official)

- Symbol: `HCM494000000ABJT`
- Footprint: `Crystal:Crystal_SMD_HC49-SD`
- 3D model: HC-49S-SMD (KiCad packages3D, STEP)
- 3D model files: `hcm494000000abjt-etched.step` / `hcm494000000abjt-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `hcm494000000abjt.step` / `hcm494000000abjt.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [CITIZEN datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588948443808718848) (2 pp, sha256 ``, retrieved 2026-10-15, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins`, primary `crystal numbering` (convention), consensus `off` (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/hcm494000000abjt-datasheet.pdf)