# KY4953

**KY** · MOSFETs · SOP-8

KY4953 from KY, in a SOP-8. 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 | S1 | passive | Source of P-channel MOSFET 1 in the dual -30 V device, which is rated for continuous drain current of -5.1 A. |
| 2 | G1 | input | Gate of P-channel MOSFET 1, with gate-source voltage rated ±20 V. |
| 3 | S2 | passive | Source of P-channel MOSFET 2 in the dual -30 V device, which is rated for continuous drain current of -5.1 A. |
| 4 | G2 | input | Gate of P-channel MOSFET 2, with gate-source voltage rated ±20 V. |
| 5 | D2 | passive | Drain of P-channel MOSFET 2; drain-source voltage rated -30 V. |
| 6 | D2 | passive | Drain of P-channel MOSFET 2 (second package pin for the same drain); drain-source voltage rated -30 V. |
| 7 | D1 | passive | Drain of P-channel MOSFET 1; drain-source voltage rated -30 V. |
| 8 | D1 | passive | Drain of P-channel MOSFET 1 (second package pin for the same drain); drain-source voltage rated -30 V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | KY |
| Package | SOP-8 |
| Category | Transistors/Thyristors |
| Pins | 8 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Drain to Source Breakdown Voltage | VDSS | -30 |  |  | V | VGS=0V, ID=-250µA | 2 |
| Drain to Source Leakage Current | IDSS |  |  | -1 | µA | VDS= -30V, VGS= 0V | 2 |
| Gate to Source Forward Leakage | IGSS | -100 |  | 100 | nA | VGS= ±20V, VDS= 0V | 2 |
| Drain-to-Source On-Resistance | RDS(ON) |  | 43 | 55 | mΩ | VGS=-10V, ID=-5.1A | 2 |
| Drain-to-Source On-Resistance | RDS(ON) |  | 55 | 90 | mΩ | VGS=-4.5V, ID=-4.2A | 2 |
| Diode Forward Voltage | VSD |  |  | -1.2 | V | IS=-5.1A, VGS=0V, TJ=25℃ | 2 |
| Gate Threshold Voltage | VGS(TH) | -1 | -1.3 | -2 | V | VDS=VGS, ID=-250µA | 2 |
| Drain-Source Voltage | VDSS |  |  | -30 | V | Ta=25℃ | 1 |
| Continuous Drain Current | ID |  |  | -5.1 | A | Ta=25℃ | 1 |
| Pulsed Drain Current | IDM |  |  | -20 | A | Ta=25℃ | 1 |
| Gate-Source Voltage | VGSS | -20 |  | 20 | V | Ta=25℃ | 1 |
| Power Dissipation | PD |  |  | 2.5 | W | Ta=25℃ | 1 |
| Operating Junction and Storage Temperature Range | TSTG | -55 |  | 150 | ℃ |  | 1 |
| Junction Temperature | TJ |  |  | 150 | ℃ |  | 1 |
| Junction-to-Ambient Thermal Resistance | RθJA |  |  | 50 | ℃/W |  | 1 |

## CAD (KiCad official)

- Symbol: `KY4953`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOP-8 (KiCad packages3D, STEP)
- 3D model files: `ky4953-etched.step` / `ky4953-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ky4953.step` / `ky4953.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [KY datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590233613967908864) (5 pp, sha256 `23f48cc68aa5d5f2`, retrieved 2026-10-17, tier: lcsc)
- **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:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/ky4953-datasheet.pdf)