Microchip Technology 25AA080CT-I/ST

Overview

25AA080CT-I/ST from Microchip Technology is an 8 Kbit SPI Serial EEPROM with 1024 × 8-bit organization, 16-byte page size, and 1.8–5.5 V supply range. It supports up to 10 MHz clock frequency, delivers 5 mA max read/write current at 5.5 V, and operates across -40°C to +85°C for industrial applications - used for firmware storage, calibration data retention, and configuration memory in microcontroller-based systems.

For engineers reviewing the 25AA080CT-I/ST datasheet, 25AA080CT-I/ST pinout, 25AA080CT-I/ST application, or 25AA080CT-I/ST equivalent, key selection criteria include SPI timing compliance at 1.8 V, hardware write protection via WP pin and STATUS register, page-write capability within 16-byte boundaries, and TSSOP-8 packaging suitability for space-constrained PCB layouts.

Technical Context

The 25AA080CT-I/ST implements a standard SPI Mode 0,0 (CPOL = 0, CPHA = 0) interface with separate SI and SO lines, CS-controlled device selection, and HOLD pin support for interrupt-safe transaction suspension. Its internal architecture includes a write-enable latch, nonvolatile STATUS register with BP0/BP1 block protection bits, and automatic self-timed erase/write cycles completing in ≤5 ms.

It features dual-level write protection: software-controlled via WREN/WRSR instructions and hardware-enforced when WP pin is low and WPEN bit is set. The device powers on with WEL reset and SO in high-impedance state, requiring explicit CS assertion and instruction sequencing to initiate any operation - ensuring robust immunity against spurious writes during power transitions.

Key Specifications

Pinout & Package

25AA080CT-I/ST is housed in an 8-lead TSSOP package (4.4 mm body width, 0.65 mm pitch), RoHS-compliant and Pb-free, optimized for automated surface-mount assembly and thermal performance in compact industrial modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SPI Serial EEPROM applications.

Compared with 25AA080CT-I/ST, the 25LC080CT-I/ST offers higher voltage margin and larger page size at the cost of 1.8 V operation loss, while AT25080B-SSHL-T trades HOLD support and Microchip-specific protection logic for wider SPI mode flexibility and alternate vendor sourcing.

Availability

25AA080CT-I/ST is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, automotive body electronics, and smart metering applications requiring stable component supply, long-term obsolescence planning, and RoHS-compliant manufacturing.

Supply support for 25AA080CT-I/ST includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 25AA080C/D family was designed specifically for reliable, low-voltage SPI-based nonvolatile storage in cost-sensitive, space-constrained embedded systems - emphasizing write safety, extended temperature operation, and seamless integration with Microchip's PIC® MCU ecosystem.

FAQ

What is the maximum clock frequency supported by the 25AA080CT-I/ST across its full voltage range?

The 25AA080CT-I/ST supports up to 10 MHz at VCC ≥ 4.5 V, 5 MHz at 2.5 V ≤ VCC < 4.5 V, and 3 MHz at 1.8 V ≤ VCC < 2.5 V. These values are specified in Table 1-2 of the DS22151B datasheet and reflect guaranteed AC timing margins under industrial temperature conditions. The 25AA080CT-I/ST must be configured with appropriate SCK period and setup/hold times per voltage bin to maintain reliable communication.

Does the 25AA080CT-I/ST support hardware write protection, and how is it enabled?

Yes, the 25AA080CT-I/ST supports hardware write protection using the WP pin in conjunction with the WPEN bit in the STATUS register. Protection is active only when WP is low AND WPEN = 1. When enabled, it prevents writes to the nonvolatile STATUS register bits (BP0, BP1, WPEN) while allowing normal memory reads and writes. The 25AA080CT-I/ST defaults to WPEN = 0 at power-up, so WP pin grounding alone has no effect until WPEN is explicitly set via WRSR.

What is the page size of the 25AA080CT-I/ST, and why does it matter for firmware implementation?

The 25AA080CT-I/ST has a fixed 16-byte page size, meaning up to 16 consecutive bytes can be written in a single page-write command. This matters because crossing a 16-byte boundary during a page write causes data to wrap to the start of the same page instead of advancing - potentially overwriting prior data. Firmware must validate address alignment and split multi-page writes explicitly. The 25AA080CT-I/ST's 'C' suffix denotes this 16-byte page configuration, distinguishing it from 'D' variants with 32-byte pages.

How does the HOLD pin function on the 25AA080CT-I/ST, and what are the timing constraints?

The HOLD pin on the 25AA080CT-I/ST suspends ongoing SPI communication without resetting internal state. To activate HOLD, the pin must be driven low while SCK is low; otherwise, suspension waits until the next SCK high-to-low transition. While held, SI, SCK, and SO enter high-impedance, and input transitions are ignored except for CS. Resumption requires HOLD high while SCK is low. These constraints ensure deterministic behavior during MCU interrupt servicing - a key reliability feature of the 25AA080CT-I/ST.

What is the endurance and data retention specification for the 25AA080CT-I/ST, and under what conditions are they guaranteed?

The 25AA080CT-I/ST guarantees >1 million erase/write cycles and >200 years of data retention at 25°C, based on characterization per Note 3 in DS22151B. Endurance is tested at VCC = 5.5 V and TA = 25°C; retention assumes storage at ambient temperature with no bias stress. Real-world performance may vary with elevated temperature or voltage derating, but the 25AA080CT-I/ST's specifications exceed typical industrial requirements for long-life embedded deployments.