| Pin | Symbol | Type | Function (EN) |
|---|---|---|---|
| 1 | CS | I/O | Multiplexed I/O & Peripheral Pin CS (General) |
| 2 | SO | I/O | Multiplexed I/O & Peripheral Pin SO (General) |
| 3 | WP | I/O | Multiplexed I/O & Peripheral Pin WP (General) |
| 4 | VSS | GND | Ground Reference Pin (VSS) |
| 5 | SI | I/O | Multiplexed I/O & Peripheral Pin SI (General) |
| 6 | SCK | I/O | Multiplexed I/O & Peripheral Pin SCK (SPI) |
| 7 | HOLD | I/O | Multiplexed I/O & Peripheral Pin HOLD (General) |
| 8 | VCC | Power | Power Supply Input (VCC — 1.8V to 5.5V) |
25AA320A / 25AA320AX (TSSOP-8)
| Designator / Replacement MPN | Value / Package | Function & PCB Layout Rule |
|---|---|---|
| N/A BOM | Per application circuit SOIC-8 | Size power & signal trace widths for rated load current following IPC-2221 clearance rules. |
Manufactured by MICROCHIP, the 25AA320A-I/SN is housed in a SOIC-8 package with 8 pins and a 1.27 mm lead pitch, supporting a VCC supply range of 1.8V to 5.5V. Key pins include: 1 (CS: Multiplexed I/O & Peripheral Pin CS (General)), 2 (SO: Multiplexed I/O & Peripheral Pin SO (General)), 3 (WP: Multiplexed I/O & Peripheral Pin WP (General)), 4 (VSS: Ground Reference Pin (VSS)), 5 (SI: Multiplexed I/O & Peripheral Pin SI (General)), 6 (SCK: Multiplexed I/O & Peripheral Pin SCK (SPI)).
Normalized from the official datasheet mechanical drawing per IPC-7351B (Density Level B Nominal), 25AA320A-I/SN (SOIC-8) has a nominal body envelope of 3.90 × 4.90 mm, pitch e = 1.27 mm, and 8 copper pads.
You can download the verified open-hardware (CERN-OHL-P-2.0) CAD library bundle for 25AA320A-I/SN (MICROCHIP, SOIC-8) directly on this page, including KiCad 8 Footprints (.kicad_mod), Schematic Symbols (.kicad_sym), Autodesk Fusion 360 / Eagle (.lbr), and 3D STEP AP214 / WebGL GLB models.
| Pin # | Signal Name | Electrical Type | Functional Description & Design Notes |
|---|---|---|---|
| 1 | CS | Digital_IO | Signal terminal CS (I/O, 1.8V to 5.5V domain). Multiplexed alternate functions: CS. Supported peripheral buses: General. |
| 2 | SO | Digital_IO | Signal terminal SO (I/O, 1.8V to 5.5V domain). Multiplexed alternate functions: SO. Supported peripheral buses: General. |
| 3 | WP | Digital_IO | Signal terminal WP (I/O, 1.8V to 5.5V domain). Multiplexed alternate functions: WP. Supported peripheral buses: General. |
| 4 | VSS | GND | 0V electrical ground return terminal (VSS) for internal core logic, I/O drivers, and analog sub-blocks. |
| 5 | SI | Digital_IO | Signal terminal SI (I/O, 1.8V to 5.5V domain). Multiplexed alternate functions: SI. Supported peripheral buses: General. |
| 6 | SCK | Digital_IO | Signal terminal SCK (I/O, 1.8V to 5.5V domain). Multiplexed alternate functions: SCK. Supported peripheral buses: SPI. |
| 7 | HOLD | Digital_IO | Signal terminal HOLD (I/O, 1.8V to 5.5V domain). Multiplexed alternate functions: HOLD. Supported peripheral buses: General. |
| 8 | VCC | Power_In | Primary positive power supply input (VCC) operating in the 1.8V to 5.5V domain (Max rating: 5.5V). |