# BZX84-B43

**Nexperia** · Zener Diodes · SOT-23(TO-236AB)

BZX84-B43 from Nexperia, in a SOT-23(TO-236AB). Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model). Symbol and footprint from KiCad-official CAD; the 3D model is generated from the datasheet's package dimensions.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | A | passive | Anode of the voltage regulator diode; the datasheet limits the device forward current IF to 200 mA maximum (Table 5). |
| 2 | n.c. | unconnected | Not connected; the pinning table lists this pin as not connected. |
| 3 | K | passive | Cathode of the voltage regulator diode; for BZX84-B43 the working voltage VZ is 42.10 V minimum to 43.90 V maximum at IZ = 2 mA (Table 9). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Nexperia |
| Package | SOT-23(TO-236AB) |
| 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 |
|---|---|---|---|---|---|---|---|
| Working voltage (nominal, type 43) | VZ | 42.1 | 43 | 43.9 | V | IZ = 2 mA; Tj = 25 °C (BZX84-B row, Table 9) | 7 |
| Working voltage tolerance (B series) |  | -2 |  | 2 | % | BZX84-B E24 series tolerance ±2 % | 1 |
| Maximum differential resistance | rdif |  |  | 375 | Ω | IZ = 0.5 mA | 7 |
| Maximum differential resistance | rdif |  |  | 150 | Ω | IZ = 2 mA | 7 |
| Reverse current | IR |  |  | 0.05 | μA | Max VR column = 30.1 V | 7 |
| Temperature coefficient | SZ | 37.6 |  | 46.6 | mV/K | IZ = 2 mA | 7 |
| Diode capacitance | Cd |  |  | 40 | pF | f = 1 MHz; VR = 0 V | 7 |
| Non-repetitive peak reverse current | IZSM |  |  | 0.6 | A | tp = 100 μs; square wave; Tj = 25 °C | 7 |
| Forward voltage | VF |  |  | 0.9 | V | IF = 10 mA; pulse test tp ≤ 100 μs; δ ≤ 0.02 | 4 |
| Forward current | IF |  |  | 200 | mA |  | 4 |
| Non-repetitive peak reverse power dissipation | PZSM |  |  | 40 | W | tp = 100 μs; square wave; Tj = 25 °C prior to surge | 4 |
| Total power dissipation | Ptot |  |  | 250 | mW | Tamb ≤ 25 °C; FR4 PCB, standard footprint | 4 |
| Junction temperature | Tj |  |  | 150 | °C |  | 4 |
| Ambient temperature | Tamb | -55 |  | 150 | °C |  | 4 |
| Storage temperature | Tstg | -65 |  | 150 | °C |  | 4 |
| Thermal resistance junction to ambient | Rth(j-a) |  |  | 500 | K/W | in free air; FR4 PCB, single-sided 70 µm copper, standard footprint | 4 |
| Thermal resistance junction to solder point | Rth(j-sp) |  |  | 330 | K/W | soldering point of cathode tab | 4 |

## CAD (land: KiCad; 3D: generated from the datasheet)

- Symbol: `BZX84-B43`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23(TO-236AB), generated on the KiCad land (body 1.3 x 2.9 mm, terminals on the pads, 1.0 mm tall, datasheet A, midpoint of min and max). KiCad's stock model for this land is taller than the datasheet allows, so the model is generated from the datasheet drawing; 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: `bzx84-b43-etched.step` / `bzx84-b43-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bzx84-b43.step` / `bzx84-b43.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Nexperia datasheet](https://assets.nexperia.com/documents/data-sheet/BZX84-B43.pdf) (14 pp, sha256 `e6278027e055c1b0`, retrieved 2026-11-13, 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:** land: KiCad official libraries (CC-BY-SA 4.0); 3D: generated from the datasheet's package dimensions (provenance.model_3d_generated).

[Datasheet PDF](docs/bzx84-b43-datasheet.pdf)