# BL8503-25PRM

**BL Shanghai Belling** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-23-3L

BL8503-25PRM from BL Shanghai Belling, in a SOT-23-3L. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | Vss | power_in | Ground reference for the regulator. Connect to system ground. |
| 2 | Vout | power_out | Regulated output voltage (2.5V for BL8503-25PRM, factory-trimmed within +/-2%). Supplies up to 250mA. Requires a 1uF (tantalum recommended) output capacitor for loop stability. |
| 3 | Vin | power_in | Unregulated supply input. Operating range 1.5V-10V (recommended max 8V); requires at least Vout + dropout (~170mV @ 100mA, ~400mV @ 250mA). A 1uF (tantalum recommended) input capacitor is required. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | BL Shanghai Belling |
| Package | SOT-23-3L |
| Category | PMIC |
| Pins | 3 |

## Ordering variants

Same part, different packaging or reel option.

- `BL8503-25PRM`
- `BL8503-25PRMPSM`
- `BL8503-25PRMPSA`
- `BL8503-25PRMPSB`
- `BL8503-25PRMPT`

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Ambient Temperature (recommended) |  | -40 |  | 125 | C |  | 4 |
| Input Voltage Range (recommended) |  |  |  | 8 | V |  | 4 |
| Max input voltage |  |  |  | 10 | V |  | 4 |
| Junction Temperature | TJ |  |  | 125 | C |  | 4 |
| Ambient Temperature | TA | -40 |  | 85 | C |  | 4 |
| Power Dissipation |  |  |  | 0.15 | W | SOT-23-3 | 4 |
| Storage Temperature | Ts | -45 |  | 150 | C |  | 4 |
| Lead Temperature and Time |  |  |  | 260 | C | 10 s | 4 |

## CAD (KiCad official)

- Symbol: `BL8503-25PRM`
- Footprint: `Package_TO_SOT_SMD:SOT-23-3`
- 3D model: SOT-23-3L (KiCad packages3D, STEP)
- 3D model files: `bl8503-25prm-etched.step` / `bl8503-25prm-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bl8503-25prm.step` / `bl8503-25prm.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [BL Shanghai Belling datasheet](docs/bl8503-25prm-datasheet.pdf) (13 pp, sha256 `8f6684221c2cf4c4`, retrieved 2026-08-17, 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/bl8503-25prm-datasheet.pdf)