# DL4750A

**LGE** · Zener Diodes · MELF

DL4750A from LGE, in a MELF. 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 | K | passive | Cathode, marked by the cathode band on the MELF glass case; zener voltage of DL4750A is 27 V nominal at 9.5 mA test current. |
| 2 | A | passive | Anode terminal at the opposite end of the MELF glass case from the cathode band; power dissipation is 1.0 W at Tamb 50 °C. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | LGE |
| Package | MELF |
| Category | Diodes |
| 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 |
|---|---|---|---|---|---|---|---|
| Nominal zener voltage | VZ |  | 27 |  | V | IZT = 9.5 mA | 2 |
| Zener voltage tolerance (A suffix) | VZ | -5 |  | 5 | % | suffix A | 1 |
| Test current | IZT |  | 9.5 |  | mA |  | 2 |
| Maximum dynamic impedance | ZZT |  |  | 35 | Ω | @IZT | 2 |
| Maximum dynamic impedance (knee) | ZZK |  |  | 750 | Ω | @IZK = 0.25 mA | 2 |
| Forward voltage | VF |  |  | 1.2 | V | IF = 200 mA | 1 |
| Power dissipation | PDiss |  |  | 1 | W | Tamb 50, electrodes kept at ambient temperature | 1 |
| Junction temperature | TJ |  |  | 175 | °C |  | 1 |
| Storage temperature range | Ts | -55 |  | 175 | °C |  | 1 |
| Thermal resistance junction to ambient | RThJA |  |  | 170 | K/W | l=9.5mm(3/8), TL=constant | 1 |

## CAD (KiCad official)

- Symbol: `DL4750A`
- Footprint: `Diode_SMD:D_MELF`
- 3D model: MELF (KiCad packages3D, STEP)

## Provenance

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

- **Datasheet:** [LGE datasheet](docs/dl4750a-datasheet.pdf) (3 pp, sha256 `a224b6085d68189f`, retrieved 2026-10-22, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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/dl4750a-datasheet.pdf)