# BZX84C51LT1G

**onsemi** · Zener Diodes · SOT-23

BZX84C51LT1G from onsemi, in a SOT-23. 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 | ANODE | passive | Anode terminal of the Zener diode; the datasheet's SOT-23 Style 8 pinout assigns pin 1 as anode. |
| 2 | NC | unconnected | No internal connection; the datasheet specifies pin 2 as NO CONNECTION for this SOT-23 Style 8 package. |
| 3 | CATHODE | passive | Cathode terminal of the Zener diode, identified by the polarity band; the datasheet assigns pin 3 as cathode. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | onsemi |
| Package | SOT-23 |
| Category | Diodes |
| Pins | 3 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Reverse Zener Voltage (VZ1) @ IZT1 | VZ1 | 48 | 51 | 54 | V | @ IZT1 = 5 mA (Note 3) | 3 |
| Maximum Zener Impedance (ZZT1) @ IZT1 | ZZT1 |  |  | 180 | Ω | @ IZT1 = 5 mA | 3 |
| Reverse Zener Voltage (VZ2) @ IZT2 | VZ2 | 47.6 |  | 54 | V | @ IZT2 = 1 mA (Note 3) | 3 |
| Maximum Zener Impedance (ZZT2) @ IZT2 | ZZT2 |  |  | 400 | Ω | @ IZT2 = 1 mA | 3 |
| Reverse Zener Voltage (VZ3) @ IZT3 | VZ3 | 48.1 |  | 54.6 | V | @ IZT3 = 20 mA (Note 3) | 3 |
| Maximum Zener Impedance (ZZT3) @ IZT3 | ZZT3 |  |  | 100 | Ω | @ IZT3 = 20 mA | 3 |
| Maximum Reverse Leakage Current | IR |  |  | 0.05 | µA | @ VR = 35.7 V | 3 |
| Maximum Temperature Coefficient of VZ (min) | VZ | 46.6 |  |  | mV/k | @ IZT1 = 5 mA | 3 |
| Maximum Temperature Coefficient of VZ (max) | VZ |  |  | 57.2 | mV/k | @ IZT1 = 5 mA | 3 |
| Maximum Capacitance | C |  |  | 40 | pF | @ VR = 0, f = 1 MHz | 3 |
| Total Power Dissipation on FR-5 Board | PD |  |  | 250 | mW | FR-5 board, TA = 25°C (Note 1) | 2 |
| Thermal Resistance, Junction-to-Ambient (FR-5 Board) | RJA |  |  | 500 | °C/W | FR-5 board (Note 1) | 2 |
| Total Power Dissipation on Alumina Substrate | PD |  |  | 300 | mW | Alumina substrate, TA = 25°C (Note 2) | 2 |
| Thermal Resistance, Junction-to-Ambient (Alumina Substrate) | RJA |  |  | 417 | °C/W | Alumina substrate (Note 2) | 2 |
| Junction and Storage Temperature Range | TJ, Tstg | -65 |  | 150 | °C |  | 2 |

## CAD (KiCad official)

- Symbol: `BZX84C51LT1G`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23, generated from the KiCad footprint (body from the F.Fab outline, terminals on the pads, 1.0 mm tall, datasheet A, nominal). Neither the vendor nor KiCad ships a 3D model for this package, so the dimensions come from the datasheet drawing where it was read and are defaults otherwise (see provenance.model_3d_generated), not the manufacturer's CAD (STEP)
- 3D model files: `bzx84c51lt1g-etched.step` / `bzx84c51lt1g-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bzx84c51lt1g.step` / `bzx84c51lt1g.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [onsemi datasheet](https://www.onsemi.com/pdf/datasheet/bzx84c51lt1-d.pdf) (8 pp, sha256 `e8ae0892f00a3794`, retrieved 2026-11-12, tier: manufacturer)
- **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/bzx84c51lt1g-datasheet.pdf)