# ATTINY25-20SSU

**Microchip Tech** · MICROCHIP · SOIC-8

ATTINY25-20SSU from Microchip Tech, in a SOIC-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 | PB5 | bidirectional | Port B bit 5 with reset function: a low level longer than the minimum pulse length generates a reset, and the pin can also be used as a weak I/O pin. |
| 2 | PB3 | bidirectional | Port B bit 3 is a bi-directional I/O pin with internal pull-up selectable per bit, with symmetrical high sink and source drive capability. |
| 3 | PB4 | bidirectional | Port B bit 4 is a bi-directional I/O pin with internal pull-up selectable per bit, with symmetrical high sink and source drive capability. |
| 4 | GND | power_in | Ground reference for the device. |
| 5 | PB0 | bidirectional | Port B bit 0 is a bi-directional I/O pin with internal pull-up selectable per bit, with symmetrical high sink and source drive capability. |
| 6 | PB1 | bidirectional | Port B bit 1 is a bi-directional I/O pin with internal pull-up selectable per bit, with symmetrical high sink and source drive capability. |
| 7 | PB2 | bidirectional | Port B bit 2 is a bi-directional I/O pin with internal pull-up selectable per bit, with symmetrical high sink and source drive capability. |
| 8 | VCC | power_in | Supply voltage: 2.7 - 5.5V for ATtiny25/45/85 (1.8 - 5.5V for the ATtiny25V/45V/85V). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Microchip Tech |
| Package | SOIC-8 |
| Category | Embedded Processors & Controllers |
| 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 |
|---|---|---|---|---|---|---|---|
| Supply voltage (ATtiny25, 20 MHz grade, Industrial) | VCC | 2.7 |  | 5.5 | V | ATtiny25-20 ordering code, 20 MHz speed grade | 11 |
| Operating frequency vs. supply voltage |  | 0 |  | 10 | MHz | 2.7 - 5.5 V | 1 |
| Operating frequency vs. supply voltage |  | 0 |  | 20 | MHz | 4.5 - 5.5 V | 1 |
| Operating temperature range (Industrial) |  | -40 |  | 85 | °C | Industrial grade, ATtiny25-20SSU ordering code | 11 |

## Materials and finish

As the datasheet states them (page.json `metadata.appearance`; the 3D model's colours follow it).

| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| contacts |  | tin | 3. Code indicators: H = NiPdAu lead finish, U/N = matte tin, R = tape & reel. 4. Can also be supplied in wafer form. Contact your local Atmel sales office for ordering information and minimum quantiti | 11 |

## CAD (KiCad official)

- Symbol: `ATTINY25-20SSU`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `attiny25-20ssu-etched.step` / `attiny25-20ssu-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `attiny25-20ssu.step` / `attiny25-20ssu.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Microchip Tech datasheet](docs/attiny25-20ssu-datasheet.pdf) (30 pp, sha256 `31cd54bf6623a7ca`, retrieved 2026-11-05, tier: manufacturer)
- **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/attiny25-20ssu-datasheet.pdf)