# 0121M4-37.400F18DTNJL

**HCI** · Crystals · SMD2016-4P

0121M4-37.400F18DTNJL from HCI, in a SMD2016-4P. 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 | CRYSTAL | passive | Crystal terminal 1 of the AT-cut fundamental quartz unit, connects to the oscillator circuit. |
| 2 | NC/GND | passive | Not connected or ground; pads 2 and 4 are connected to the metal lid and can be left open (floating) or connected to ground. |
| 3 | CRYSTAL | passive | Crystal terminal 2 of the AT-cut fundamental quartz unit, connects to the oscillator circuit. |
| 4 | NC/GND | passive | Not connected or ground; pads 2 and 4 are connected to the metal lid and can be left open (floating) or connected to ground. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | HCI |
| Package | SMD2016-4P |
| 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 |
|---|---|---|---|---|---|---|---|
| Nominal frequency range |  | 20 |  | 60 | MHz |  | 1 |
| Equivalent series resistance | ESR |  |  | 80 | Ω | 30.000 to 39.999MHz | 1 |
| Load capacitance | CL | 6 |  | 32 | pF | or SERIES Please specify. | 1 |
| Shunt capacitance | C0 |  |  | 3 | pF |  | 1 |
| Drive level |  |  | 10 | 100 | µW |  | 1 |
| Storage temperature range | Tstg | -55 |  | 125 | °C |  | 1 |

## CAD (KiCad official)

- Symbol: `0121M4-37.400F18DTNJL`
- Footprint: `Crystal:Crystal_SMD_2016-4Pin_2.0x1.6mm`
- 3D model: SMD2016-4P (KiCad packages3D, STEP)
- 3D model files: `0121m4-37-400f18dtnjl-etched.step` / `0121m4-37-400f18dtnjl-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `0121m4-37-400f18dtnjl.step` / `0121m4-37-400f18dtnjl.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [HCI datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603385869835382784) (1 pp, sha256 `8a6e0e384ba9e6df`, 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/0121m4-37-400f18dtnjl-datasheet.pdf)