Microchip Technology 25AA1024-I/P

Overview

25AA1024-I/P from Microchip Technology Inc. is a 1-Mbit (131,072-byte) SPI serial EEPROM with byte- and page-write capability, 256-byte page size, 6 ms max internal write cycle time, and industrial temperature range (–40°C to +85°C). It operates from 1.8V to 5.5V supply and supports up to 20 MHz clock frequency at 4.5–5.5V, enabling high-speed configuration storage in microcontroller-based systems.

For engineers reviewing the 25AA1024-I/P datasheet, 25AA1024-I/P pinout, 25AA1024-I/P application, or 25AA1024-I/P equivalent, key selection considerations include its deep power-down current (1 µA at 2.5V/85°C), sector-level hardware write protection (32 KB per sector), AEC-Q100 qualification, and support for Page/Sector/Chip Erase commands-critical for firmware update resilience and secure parameter retention.

Technical Context

The 25AA1024-I/P implements a standard SPI Mode 0,0/Master-Slave interface with separate SI (data-in) and SO (data-out) lines, CS-controlled selection, and HOLD pin for transaction suspension without reset. Its internal architecture includes a 24-bit address space, status register with WIP/WEL/BP0/BP1 bits, and nonvolatile block protection logic tied to WPEN bit and physical WP pin.

It integrates self-timed erase/write cycles (6 ms page write, 10 ms sector/chip erase), electronic signature read (RDID), and deep power-down entry (DPD) with automatic wake-on-RDID. All write operations require prior WREN instruction, and write enable latch resets on power-up, WRDI, WRSR, or any successful write/erase command.

Key Specifications

Pinout & Package

25AA1024-I/P is supplied in an 8-lead PDIP package (plastic dual in-line package), with lead pitch of 0.1 inch and through-hole mounting. Pin numbering follows standard DIP convention (pin 1 = CS, pin 8 = VCC).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25LC1024-I/P and AT25DF101-SSH-T, the 25AA1024-I/P delivers superior write speed, lower deep-sleep current, and integrated hardware write locking - making it optimal for safety- or reliability-sensitive embedded applications requiring guaranteed nonvolatile parameter integrity without firmware overhead.

Availability

25AA1024-I/P is available at Aetrix Electronics and suitable for industrial PLCs, automotive ECUs, medical device configuration storage, and smart meter firmware patching requiring stable component supply across extended product lifecycles.

Supply support for 25AA1024-I/P 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 devices, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 25AA1024-I/P belongs to Microchip's serial EEPROM product line, designed specifically for reliable, low-power, and pin-compatible nonvolatile storage in resource-constrained embedded systems requiring AEC-Q100 compliance and long-term data retention.

FAQ

What is the maximum SPI clock frequency supported by the 25AA1024-I/P?

The 25AA1024-I/P supports up to 20 MHz SPI clock frequency when VCC is 4.5V to 5.5V. At 2.5V ≤ VCC < 4.5V, the maximum clock drops to 10 MHz, and at 2.0V ≤ VCC < 2.5V, it is limited to 2 MHz. These deratings ensure timing margin compliance across voltage and temperature ranges specified for the industrial grade.

Does the 25AA1024-I/P require external erase operations before writing new data?

No, the 25AA1024-I/P does not require external erase operations before writing. Its internal write cycle automatically performs page-level erase as needed. Byte and page writes execute atomically with built-in self-timed erase; only Page, Sector, or Chip Erase instructions are optional and used for bulk management-not prerequisites for writes.

How does hardware write protection work on the 25AA1024-I/P?

Hardware write protection on the 25AA1024-I/P is controlled jointly by the WP pin (Pin 3) and the WPEN bit in the STATUS register. When WPEN = 1 and WP = low, writes to nonvolatile STATUS register bits (BP0, BP1, WPEN) are blocked. Memory array writes remain enabled unless BP0/BP1 configure sector protection. If WPEN = 0, the WP pin has no effect.

What is the purpose of the HOLD pin on the 25AA1024-I/P?

The HOLD pin (Pin 7) on the 25AA1024-I/P suspends ongoing SPI communication without resetting the internal address pointer or command state. When pulled low while SCK is low, it places SO in high-impedance and ignores SI/SCK transitions, allowing the host MCU to service higher-priority interrupts and resume exactly where transmission left off.

Is the 25AA1024-I/P compatible with standard SPI Mode 0,0?

Yes, the 25AA1024-I/P is fully compatible with SPI Mode 0,0 (CPOL = 0, CPHA = 0): data is sampled on the rising edge of SCK and changed on the falling edge. It uses separate SI and SO lines (not 3-wire), requires CS-driven frame synchronization, and supports standard SPI opcodes including READ (0x03), WRITE (0x02), and RDSR (0x05) as defined in its instruction set.