# CH412Z

**TECH PUBLIC** · ESD And Surge Protection (TVS/ESD) · SOT-353

CH412Z from TECH PUBLIC, in a SOT-353. 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 | I/O1 | passive | ESD-protected I/O line 1 with steering diodes to pin 2 (GND); reverse working voltage 5V max, breakdown 6V min to 9V max at 1mA. |
| 2 | GND | power_in | Common ground connection of the 4-line TVS array, shared by all I/O steering diodes. |
| 3 | I/O2 | passive | ESD-protected I/O line 2 with steering diodes to pin 2 (GND); withstands ±30kV air and contact discharge per IEC61000-4-2. |
| 4 | I/O3 | passive | ESD-protected I/O line 3 with steering diodes to pin 2 (GND); clamping voltage 11V max at IPP=4.5A (8/20µs). |
| 5 | I/O4 | passive | ESD-protected I/O line 4 with steering diodes to pin 2 (GND); leakage 100nA max at VRWM=5V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | TECH PUBLIC |
| Package | SOT-353 |
| Category | Circuit Protection |
| Pins | 5 |

## CAD (KiCad official)

- Symbol: `CH412Z`
- Footprint: `Package_TO_SOT_SMD:SOT-353_SC-70-5`
- 3D model: SOT-353 (KiCad packages3D, STEP)
- 3D model files: `ch412z-etched.step` / `ch412z-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ch412z.step` / `ch412z.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [TECH PUBLIC datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603387079011147776) (4 pp, sha256 `d7ed3bead69fef02`, retrieved 2026-10-18, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (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/ch412z-datasheet.pdf)