Microchip Technology 25AA010A-I/ST

Overview

25AA010A-I/ST from Microchip Technology Inc. is a 1 Kbit (128 × 8) SPI serial EEPROM with 1.8–5.5 V supply, 10 MHz max clock frequency, and industrial temperature range (−40°C to +85°C). It features hardware write protection (WP pin), HOLD functionality for interrupt-safe pausing, and 16-byte page write capability. Used in microcontroller-based systems for storing calibration data, configuration settings, or firmware patches.

For engineers reviewing the 25AA010A-I/ST datasheet, 25AA010A-I/ST pinout, 25AA010A-I/ST application, or 25AA010A-I/ST equivalent, key selection criteria include its 1.8 V minimum VCC, 5 µA standby current at 5.5 V, 1 M endurance cycles, >200-year data retention, and compatibility with standard SPI master peripherals across PIC, ARM, and RISC-V platforms.

Technical Context

The 25AA010A-I/ST implements a true SPI Mode 0,0 interface (CPOL = 0, CPHA = 0) with separate SI/SO lines and active-low CS. Its internal architecture includes an 8-bit instruction register, status register with WIP/WEL/BP bits, and page latches enabling up to 16-byte writes within a single 16-byte physical page boundary (00h–0Fh, 10h–1Fh, etc.).

Write operations require explicit WREN instruction followed by CS high-to-low transition to initiate self-timed internal write cycle (≤5 ms). The HOLD pin suspends ongoing SPI transfers without resetting the sequence, while WP pin disables all nonvolatile writes when pulled low - both functions operate independently of the write enable latch state.

Key Specifications

Pinout & Package

25AA010A-I/ST is packaged in an 8-lead TSSOP (Thin Shrink Small Outline Package) with 0.65 mm pitch, body size 4.4 mm × 3.0 mm × 1.2 mm, and exposed pad option (not connected per datasheet Note 1). Pin 1 marked by laser dot; pin 1 location confirmed per DS21832H-page 30 diagram.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25LC010A-I/ST and AT25010B-SSHL-T, the 25AA010A-I/ST uniquely supports 1.8 V operation while maintaining 10 MHz speed and identical pinout - making it the only option for battery-powered or wide-input-range designs requiring full performance at lowest voltage.

Availability

25AA010A-I/ST is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, and smart energy meter firmware patch storage requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for 25AA010A-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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory products, with a focus on embedded control and connectivity solutions.

The 25AA010A-I/ST belongs to Microchip's legacy SPI EEPROM product line designed for reliable, low-power nonvolatile storage in resource-constrained microcontroller systems - emphasizing ease of integration, long-term data integrity, and industrial-grade robustness.

FAQ

What is the minimum supply voltage required for reliable operation of the 25AA010A-I/ST?

The 25AA010A-I/ST operates reliably down to 1.8 V across its full industrial temperature range (−40°C to +85°C), as specified in Table 1-1 of DS21832H. At 1.8 V, maximum clock frequency reduces to 3 MHz, and standby current is 1 µA (TA = +85°C). This makes 25AA010A-I/ST suitable for battery-powered or energy-harvesting applications where rail voltage may sag below 2.5 V.

How does the HOLD pin function during an active SPI read sequence in the 25AA010A-I/ST?

When HOLD is pulled low during an active SPI read sequence, the 25AA010A-I/ST immediately places SO in high-impedance state and ignores further SCK transitions, freezing the internal address counter. Communication resumes from the exact byte position when HOLD returns high while SCK is low - no reinitialization or restart is needed. This behavior is confirmed in Section 2.1 and Figure 1-1 of DS21832H.

Can the 25AA010A-I/ST be used as a direct replacement for the 25LC010A-I/ST in an existing design?

The 25AA010A-I/ST is pin-compatible and functionally identical to the 25LC010A-I/ST in all respects except supply voltage range: 25AA010A-I/ST supports 1.8–5.5 V, while 25LC010A-I/ST requires 2.5–5.5 V. If the host system guarantees VCC ≥2.5 V at all times, substitution is safe; however, if VCC may dip below 2.5 V (e.g., during brown-out), the 25AA010A-I/ST provides guaranteed operation where 25LC010A-I/ST would fail.

What happens to the write enable latch after issuing a WRITE instruction in the 25AA010A-I/ST?

Per Section 2.3 and Table 2-4 of DS21832H, the write enable latch (WEL bit) in the 25AA010A-I/ST is automatically reset upon successful completion of any WRITE, WRSR, or WRDI instruction - including byte, page, or status register writes. This prevents unintended subsequent writes unless WREN is explicitly reissued, enhancing data integrity in interrupt-driven or multi-threaded firmware.

How is block write protection configured on the 25AA010A-I/ST, and what addresses does it cover?

Block write protection on the 25AA010A-I/ST is set via the BP1/BP0 bits in the STATUS register using the WRSR instruction. As defined in Table 2-3, BP1/BP0 = 00 protects none, 01 protects upper 1/4 (60h–7Fh), 10 protects upper 1/2 (40h–7Fh), and 11 protects all addresses (00h–7Fh). Protection is nonvolatile and persists through power cycles - critical for safeguarding factory calibration or boot code.