# LY5802

**Lingyang Micro** · Power Distribution Switches · SOT-23-6

LY5802 from Lingyang Micro, in a SOT-23-6. 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 | AGND | power_in | Analog ground, to be connected to the USB input ground only (not to the protected-side DR ground). |
| 2 | FB | input | Overvoltage-protection setpoint reference; the OVP threshold is set by an external divider (VOVP = 0.54 V × (R1+R2)/R2, with VFB 0.49 V min, 0.54 V typ, 0.59 V max) or by a Zener plus resistor, and the OVP setpoint should be kept below 12 V. |
| 3 | PGND | power_in | Power ground, to be connected to the USB input ground only (not to the protected-side DR ground). |
| 4 | DR | passive | Output negative terminal connected to the ground of the downstream protected circuit, must not be tied to the USB input ground; drain leakage is 1 µA max at DR = 30 V in overvoltage-protection mode. |
| 5 | VIN | power_in | Power input connected to the USB input positive supply and the protected circuit positive supply; absolute maximum input voltage is 30 V (-0.3 V to 30 V). |
| 6 | VIN | power_in | Power input connected to the USB input positive supply and the protected circuit positive supply; absolute maximum input voltage is 30 V (-0.3 V to 30 V). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Lingyang Micro |
| Package | SOT-23-6 |
| Category | Power Management (PMIC) |
| Pins | 6 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| 最高输入电压 (maximum input voltage) |  | -0.3 |  | 30 | V |  | 3 |
| 储存温度 (storage temperature) |  | -50 |  | 150 | ℃ |  | 3 |
| 工作结温 (operating junction temperature) |  | -25 |  | 125 | ℃ |  | 3 |
| 最大功耗 (maximum power dissipation) |  |  |  | 0.4 | W |  | 3 |
| FB 反馈电压 (FB feedback voltage) | VFB | 0.49 | 0.54 | 0.59 | V |  | 3 |
| 开关内阻 (switch on-resistance) | Rdson |  | 35 | 50 | mΩ | VIN=5V，Id=1A | 3 |
| 最大导通电流 (maximum on-state current) | IMAX |  |  | 2.5 | A | VIN=5V | 3 |
| DR 漏电流 (DR leakage current) | IDSS |  |  | 1 | uA | DR=30V，过压保护模式 | 3 |
| 稳压管电流 (zener diode current rating for FB zener mode) |  | 5 |  |  | mA | FB接稳压管与电阻方式，建议使用6.1V稳压管，稳压管电流规格大于5mA即可 | 4 |

## CAD (KiCad official)

- Symbol: `LY5802`
- Footprint: `Package_TO_SOT_SMD:SOT-23-6`
- 3D model: SOT-23-6 (KiCad packages3D, STEP)
- 3D model files: `ly5802-etched.step` / `ly5802-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ly5802.step` / `ly5802.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Lingyang Micro datasheet](docs/ly5802-datasheet.pdf) (5 pp, sha256 `a800f9474c9b972c`, retrieved 2026-10-18, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **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/ly5802-datasheet.pdf)