# GBU4M

**LRC** · Bridge Rectifiers · GBU

GBU4M from LRC, in a GBU. 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 | - | passive | DC negative output of the bridge, marked '-' on the package body; reverse voltage rating is 1000V for GBU4M with 4A average forward current. |
| 2 | AC1 | passive | AC input terminal, marked '~' on the package body; RMS input voltage up to 700V for GBU4M. |
| 3 | AC2 | passive | AC input terminal, marked '~' on the package body; RMS input voltage up to 700V for GBU4M. |
| 4 | + | passive | DC positive output of the bridge, marked '+' on the package body; average rectified output current 4A (Tc=100℃). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | LRC |
| Package | GBU |
| Category | Diodes |
| 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 |
|---|---|---|---|---|---|---|---|
| Maximum repetitive peak reverse voltage | VRRM |  |  | 1000 | V |  | 1 |
| Maximum RMS voltage | VRMS |  |  | 700 | V |  | 1 |
| Maximum non-repetitive voltage |  |  |  | 1100 | V |  | 1 |
| Maximum DC blocking voltage | VDC |  |  | 1000 | V |  | 1 |
| Maximum DC reverse current at rated DC blocking voltage | IR |  |  | 5 | µA | TA=25℃ | 1 |
| Maximum DC reverse current at rated DC blocking voltage | IR |  |  | 500 | µA | TA=125℃ | 1 |
| Maximum average forward rectified output current | Io |  |  | 4 | A | Tc=100℃(1) | 1 |
| Maximum average forward rectified output current (unit mounted on P.C.B. without heat-sink) | Io |  |  | 3 | A | Ta=40℃(2) | 1 |
| Peak forward surge current 8.3ms single half sine-wave superimposed on rated load | IFSM |  |  | 150 | A | 8.3ms single half sine-wave superimposed on rated load | 1 |
| Rating of fusing | I2t |  |  | 93 | A2sec | t<8.3ms | 1 |
| Dielectric strength terminals to case | Vdia |  |  | 2.5 | KV | AC 1 minute, Current 1mA | 1 |
| Max instantaneous forward voltage | VF |  |  | 1.05 | V | at 2.0A | 1 |
| Maximum thermal resistance junction to ambient per leg (on P.C.B. without heat-sink) | RθJA |  |  | 22 | ℃/W | on P.C.B. without heat-sink | 1 |
| Maximum thermal resistance junction to case per leg (on Al plate heat-sink) | RθJC |  |  | 3.5 | ℃/W | per leg on Al plate heat-sink | 1 |
| Operating junction temperature | TJ | -55 |  | 150 | ℃ |  | 1 |
| Storage temperature | Tstg | -55 |  | 150 | ℃ |  | 1 |
| Mounting torque rating | Tor |  |  | 0.8 | N.m | Rating torque | 1 |
| Suggested mounting torque | Tor | 0.45 |  | 0.65 | N.m |  | 1 |

## CAD (KiCad official)

- Symbol: `GBU4M`
- Footprint: `Diode_THT:Diode_Bridge_Vishay_GBU`
- 3D model: GBU (KiCad packages3D, STEP)
- 3D model files: `gbu4m-etched.step` / `gbu4m-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `gbu4m.step` / `gbu4m.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [LRC datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590223449529749504) (4 pp, sha256 `f4df8f6ab99b1449`, 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/gbu4m-datasheet.pdf)