# FMMT458

**YONGYUTAI** · Bipolar (BJT) · SOT-23

FMMT458 from YONGYUTAI, 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 | BASE | input | Base terminal of the NPN transistor; IB max 200 mA, VEBO max 5 V. |
| 2 | EMITTER | passive | Emitter terminal of the NPN transistor; VEBO max 5 V. |
| 3 | COLLECTOR | passive | Collector terminal of the NPN transistor; VCEO and VCBO 400 V, continuous IC 225 mA, peak ICM 1 A. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | YONGYUTAI |
| Package | SOT-23 |
| Category | Transistors/Thyristors |
| 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 |
|---|---|---|---|---|---|---|---|
| Collector-Emitter Voltage | VCEO |  |  | 400 | V |  | 1 |
| Collector-Base Voltage | VCBO |  |  | 400 | V |  | 1 |
| Emitter-Base Voltage | VEBO |  |  | 5 | V |  | 1 |
| Continuous Collector Current | IC |  |  | 225 | mA |  | 1 |
| Peak Pulse Current | ICM |  |  | 1 | A |  | 1 |
| Base Current | IB |  |  | 200 | mA |  | 1 |
| Power Dissipation | Ptot |  |  | 500 | mW | Tamb=25°C | 1 |
| Operating and Storage Temperature Range | Tj:Tstg | -55 |  | 150 | °C |  | 1 |
| Collector-Base Breakdown Voltage | V(BR)CBO | 400 |  |  | V | IC=100A | 1 |
| Collector-Emitter Breakdown Voltage | VCEO(sus) | 400 |  |  | V | IC=10mA* | 1 |
| Emitter-Base Breakdown Voltage | V(BR)EBO | 5 |  |  | V | IE=100A | 1 |
| Collector Cut-Off Current | ICBO |  |  | 100 | nA | VCB=320V | 1 |
| Emitter Cut-Off Current | IEBO |  |  | 100 | nA | VEB=4V | 1 |
| Collector-Emitter Saturation Voltage | VCE(sat) |  |  | 0.2 | V | IC=20mA, IB=2mA* | 1 |
| Collector-Emitter Saturation Voltage | VCE(sat) |  |  | 0.5 | V | IC=50mA, IB=6mA* | 1 |
| Base-Emitter Saturation Voltage | VBE(sat) |  |  | 0.9 | V | IC=50mA, IB=5mA* | 1 |
| Base-Emitter Turn On Voltage | VBE(on) |  |  | 0.9 | V | IC=50mA, VCE=10V* | 1 |
| Static Forward Current Transfer Ratio | hFE | 100 |  |  |  | IC=1mA, VCE=10V | 1 |
| Static Forward Current Transfer Ratio | hFE | 15 |  |  |  | IC=100mA, VCE=10V* | 1 |
| Static Forward Current Transfer Ratio | hFE |  |  | 300 |  |  | 1 |
| Transition Frequency | fT | 50 |  |  | MHz | IC=10mA, VCE=20V; f=20MHz | 1 |
| Output Capacitance | Cobo |  |  | 5 | pF | VCB=20V, f=1MHz | 1 |
| Turn-On Time | ton |  | 135 |  | ns | IC=50mA, VCC=100V, IB1=5mA, IB2=-10mA | 1 |
| Turn-Off Time | toff |  | 2260 |  | ns | IC=50mA, VCC=100V, IB1=5mA, IB2=-10mA | 1 |

## CAD (KiCad official)

- Symbol: `FMMT458`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `fmmt458-etched.step` / `fmmt458-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `fmmt458.step` / `fmmt458.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [YONGYUTAI datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8757281717357301760) (3 pp, sha256 `8b9362de585ffc4d`, retrieved 2026-10-18, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+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/fmmt458-datasheet.pdf)