# AT21CS01-STUM10-T

**Microchip Tech** · EEPROM · SOT-23-3

AT21CS01-STUM10-T from Microchip Tech, in a SOT-23-3. 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 | SI/O | bidirectional | Open-drain serial input/output pin that must be pulled high through an external pull-up resistor, may be wire-ORed with other open-drain devices, and also powers the device from a pull-up voltage of 1.7V to 3.6V for AT21CS01 (2.7V to 4.5V for AT21CS11). |
| 2 | NC | unconnected | No connect; this pin is not connected internally and is listed as NC for the 3-lead SOT23 package in Table 1-1. |
| 3 | GND | power_in | Ground reference for the power supply, which should be connected to the system ground. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Microchip Tech |
| Package | SOT-23-3 |
| Category | Memory |
| Pins | 3 |

## CAD (KiCad official)

- Symbol: `AT21CS01-STUM10-T`
- Footprint: `Package_TO_SOT_SMD:SOT-23-3`
- 3D model: SOT-23-3 (KiCad packages3D, STEP)
- 3D model files: `at21cs01-stum10-t-etched.step` / `at21cs01-stum10-t-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `at21cs01-stum10-t.step` / `at21cs01-stum10-t.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Microchip Tech datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588915029609484288) (47 pp, sha256 `f03eb80197165397`, retrieved 2026-10-09, 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/at21cs01-stum10-t-datasheet.pdf)