# 24LC128T-E

**Microchip Tech** · EEPROM · SOIC-8

24LC128T-E 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 | A0 | input | User-configurable chip address input that must be tied to VCC or VSS, used to select among up to eight devices on the same bus. |
| 2 | A1 | input | User-configurable chip address input that must be tied to VCC or VSS, used to select among up to eight devices on the same bus. |
| 3 | A2 | input | User-configurable chip address input that must be tied to VCC or VSS, used to select among up to eight devices on the same bus. |
| 4 | VSS | power_in | Ground. |
| 5 | SDA | bidirectional | Open-drain bidirectional serial data/address line that needs a pull-up resistor to VCC (typically 10 kΩ for 100 kHz, 2 kΩ for 400 kHz and 1 MHz). |
| 6 | SCL | input | Serial clock input that synchronizes data transfer to and from the device. |
| 7 | WP | input | Write-protect input that must be tied to VSS (writes enabled) or VCC (writes inhibited, reads unaffected). |
| 8 | VCC | power_in | Power supply input, 2.5V to 5.5V for the 24LC128. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Microchip Tech |
| Package | SOIC-8 |
| Category | Memory |
| 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 (E-temp) | VCC | 2.5 |  | 5.5 | V | Extended (E) | 3 |
| Operating temperature (E) | TA | -40 |  | 125 | °C | Extended (E) | 3 |
| Storage temperature |  | -65 |  | 150 | °C |  | 3 |
| Ambient temperature with power applied |  | -40 |  | 125 | °C |  | 3 |
| ESD protection on all pins |  | 4 |  |  | kV |  | 3 |
| High-level input voltage | VIH | 0.7 |  |  | VCC |  | 3 |
| Low-level input voltage | VIL |  |  | 0.3 | VCC | VCC ≥ 2.5V | 3 |
| Hysteresis of Schmitt trigger inputs | VHYS | 0.05 |  |  | VCC | VCC ≥ 2.5V (Note 1) | 3 |
| Low-level output voltage | VOL |  |  | 0.4 | V | IOL = 3.0 mA @ VCC = 4.5V; IOL = 2.1 mA @ VCC = 2.5V | 3 |
| Input leakage current | ILI | -1 |  | 1 | µA | VIN = VSS or VCC | 3 |
| Output leakage current | ILO | -1 |  | 1 | µA | VOUT = VSS or VCC | 3 |
| Pin capacitance | CIN, COUT |  |  | 10 | pF | VCC = 5.0V, TA = +25°C, FCLK = 1 MHz (Note 1) | 3 |
| Read operating current | ICC Read |  |  | 400 | µA | VCC = 5.5V, SCL = 400 kHz | 3 |
| Write operating current | ICC Write |  |  | 3 | mA | VCC = 5.5V | 3 |
| Standby current (E-temp) | ICCS |  |  | 5 | µA | SDA = SCL = VCC = 5.5V, A0, A1, A2, WP = VSS, E-Temp | 3 |
| Clock frequency | FCLK |  |  | 400 | kHz | 2.5V ≤ VCC ≤ 5.5V | 4 |
| Clock high time | THIGH | 600 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 4 |
| Clock low time | TLOW | 1300 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 4 |
| SDA and SCL rise time | TR |  |  | 300 | ns | 2.5V ≤ VCC ≤ 5.5V (Note 1) | 4 |
| SDA and SCL fall time | TF |  |  | 300 | ns | All except 24FC128 (Note 1) | 4 |
| Start condition hold time | THD:STA | 600 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 4 |
| Start condition setup time | TSU:STA | 600 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 4 |
| Data input hold time | THD:DAT | 0 |  |  | ns | Note 2 | 4 |
| Data input setup time | TSU:DAT | 100 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 4 |
| Stop condition setup time | TSU:STO | 600 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 4 |
| WP setup time | TSU:WP | 600 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 5 |
| WP hold time | THD:WP | 1300 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 5 |
| Output valid from clock | TAA |  |  | 900 | ns | 2.5V ≤ VCC ≤ 5.5V (Note 2) | 5 |
| Bus free time | TBUF | 1300 |  |  | ns | 2.5V ≤ VCC ≤ 5.5V | 5 |
| Output fall time from VIH min to VIL max | TOF |  |  | 250 | ns | CB ≤ 100 pF, All except 24FC128 (Note 1); min 10 + 0.1CB | 5 |
| Input filter spike suppression (SDA and SCL) | TSP |  |  | 50 | ns | All except 24FC128 (Notes 1 and 3) | 5 |
| Write cycle time (byte or page) | TWC |  |  | 5 | ms |  | 5 |
| Endurance |  | 1e+06 |  |  | cycles | +25°C, 5.5V, Page Mode (Note 4) | 5 |

## 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 | 8-Lead Plastic Small Outline (SN) - Narrow, 3.90 mm (.150 In.) Body [SOIC] A A2 | 25 |

## CAD (KiCad official)

- Symbol: `24LC128T-E`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `24lc128t-e-etched.step` / `24lc128t-e-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `24lc128t-e.step` / `24lc128t-e.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Microchip Tech datasheet](docs/24lc128t-e-datasheet.pdf) (42 pp, sha256 `7563b7f0ab4e94a7`, retrieved 2026-10-23, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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/24lc128t-e-datasheet.pdf)