# HFMMT618TA

**HXY MOSFET** · Bipolar (BJT) · SOT-23

HFMMT618TA from HXY MOSFET, 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 | B | input | Base; Emitter-Base voltage limited to 5 V max, base current IB up to 2 A. |
| 2 | E | passive | Emitter; Emitter-Base breakdown voltage V(BR)EBO is 5 V min. |
| 3 | C | passive | Collector; VCBO and VCEO are 20 V max, collector current IC is 2.5 A max. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | HXY MOSFET |
| 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-base breakdown voltage | V(BR)CBO | 20 |  |  | V | IC=100μA, IE=0 | 1 |
| Collector-emitter breakdown voltage | V(BR)CEO | 20 |  |  | V | IC=10mA, IB=0 (note 1) | 1 |
| Emitter-base breakdown voltage | V(BR)EBO | 5 |  |  | V | IE=100μA, IC=0 | 1 |
| Collector cut-off current | ICBO |  |  | 100 | nA | VCB=16V, IE=0 | 1 |
| Emitter cut-off current | IEBO |  |  | 100 | nA | VEB=4V, IC=0 | 1 |
| DC current gain 1 | hFE(1) | 200 |  |  |  | VCE=2V, IC=10mA (note 1) | 1 |
| DC current gain 2 | hFE(2) | 300 |  |  |  | VCE=2V, IC=0.2A (note 1) | 1 |
| DC current gain 3 | hFE(3) | 200 |  |  |  | VCE=2V, IC=2A (note 1) | 1 |
| DC current gain 4 | hFE(4) | 100 |  |  |  | VCE=2V, IC=4A (note 1) | 1 |
| Collector-emitter saturation voltage 1 | VCE(sat)1 |  |  | 15 | mV | IC=0.1A, IB=10mA (note 1) | 1 |
| Collector-emitter saturation voltage 2 | VCE(sat)2 |  |  | 150 | mV | IC=1A, IB=10mA (note 1) | 1 |
| Collector-emitter saturation voltage 3 | VCE(sat)3 |  |  | 200 | mV | IC=2A, IB=0mA (note 1) | 1 |
| Base-emitter saturation voltage | VBE(sat) |  |  | 1 | V | IC=2A, IB=50mA (note 1) | 1 |
| Base-emitter on voltage | VBE(on) |  |  | 1 | V | IC=2A, VCE=2V (note 1) | 1 |
| Output capacitance | Cob |  |  | 30 | pF | VCB=10V, f=1MHz | 1 |
| Turn-on time | t(on) |  |  | 170 | ns | VCC=10V, IC=1A, IB1=-IB2=10mA | 1 |
| Turn-off time | t(off) |  |  | 400 | ns | VCC=10V, IC=1A, IB1=-IB2=10mA | 1 |
| Transition frequency | fT | 100 |  |  | MHz | VCE=10V, IC=50mA, f=100MHz | 1 |
| Collector-base voltage | VCBO |  |  | 20 | V | Ta=25℃ | 1 |
| Collector-emitter voltage | VCEO |  |  | 20 | V | Ta=25℃ | 1 |
| Emitter-base voltage | VEBO |  |  | 5 | V | Ta=25℃ | 1 |
| Collector current | IC |  |  | 2.5 | A | Ta=25℃ | 1 |
| Base current (listed as Collector Current) | IB |  |  | 2 | A | Ta=25℃ | 1 |
| Collector power dissipation | PC |  |  | 350 | mW | Ta=25℃ | 1 |
| Operation junction and storage temperature range | TJ, Tstg | -55 |  | 150 | ℃ |  | 1 |
| Thermal resistance junction to ambient | RΘJA |  |  | 500 | ℃/W |  | 1 |

## CAD (KiCad official)

- Symbol: `HFMMT618TA`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `hfmmt618ta-etched.step` / `hfmmt618ta-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `hfmmt618ta.step` / `hfmmt618ta.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [HXY MOSFET datasheet](docs/hfmmt618ta-datasheet.pdf) (4 pp, sha256 `762ca511c56d4a1b`, retrieved 2026-10-26, 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/hfmmt618ta-datasheet.pdf)