Microchip Technology AT25P1024C1-10CI-1.8

Overview

AT25P1024C1-10CI-1.8 from Microchip Technology (formerly Atmel) is a 1 Mbit SPI serial EEPROM organized as 131,072 × 8 bits, supporting 1.8 V to 3.6 V operation, 2.1 MHz clock rate, and 128-byte page write mode. It features hardware/software write protection, HOLD pin for serial suspend, and operates across -40°C to +85°C for industrial embedded control and sensor data logging.

For engineers reviewing the AT25P1024C1-10CI-1.8 datasheet, AT25P1024C1-10CI-1.8 pinout, AT25P1024C1-10CI-1.8 application, or AT25P1024C1-10CI-1.8 equivalent, key selection criteria include low-voltage SPI compatibility, block-level write protection granularity, self-timed 5 ms write cycle, and 8-pad LAP package suitability for space-constrained PCB layouts.

Technical Context

The AT25P1024C1-10CI-1.8 implements a synchronous SPI slave interface with dedicated SI/SO pins, supports only SPI Modes 0 and 3, and requires WREN instruction before any write operation. Its status register controls BP0/BP1 for 1/4, 1/2, or full-array protection and WPEN for hardware write protect enable/disable.

It uses a 3-wire serial interface (CS, SCK, SI/SO), employs MSB-first data transfer, and relies on CS falling edge to initiate command decoding. The HOLD pin suspends ongoing transfers without resetting the sequence, while WP pin-when enabled-blocks status register writes when pulled low.

Key Specifications

Pinout & Package

AT25P1024C1-10CI-1.8 is packaged in an 8-pad Leadless Array Package (LAP), 0.300" wide, with exposed pad not electrically connected. This compact surface-mount package measures 4.90 mm × 3.90 mm × 1.12 mm and supports reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25P1024C1-10CI-1.8, M95M01-RMN6TP offers faster clocking but sacrifices HOLD functionality and fine-grained protection, while BR24G1M-3A trades SPI simplicity for I²C compatibility and byte-level writes-neither provides identical 1.8 V–3.6 V optimized page-write behavior with suspend and multi-level hardware lock.

Availability

AT25P1024C1-10CI-1.8 is available at Aetrix Electronics and suitable for industrial sensor nodes, programmable logic controller (PLC) I/O modules, and automotive body control modules requiring stable component supply, long-life data retention, and low-voltage SPI compatibility.

Supply support for AT25P1024C1-10CI-1.8 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 acquired Atmel in 2016 and maintains full product support, documentation, and manufacturing continuity for legacy Atmel serial EEPROMs including the AT25P1024 family.

The AT25P1024 series was designed for industrial and commercial systems needing robust, low-voltage serial nonvolatile memory with flexible hardware/software protection - especially where space, power, and data integrity are critical.

FAQ

What voltage range does the AT25P1024C1-10CI-1.8 support, and how does it affect system design?

The AT25P1024C1-10CI-1.8 operates from 1.8 V to 3.6 V, enabling direct integration with 1.8 V and 3.3 V microcontrollers without level-shifting circuitry. This simplifies power domain partitioning and reduces BOM cost. Its specified DC and AC characteristics-including 2.1 MHz max clock and 5 ms write cycle-are guaranteed across this full range, ensuring consistent timing behavior regardless of rail voltage within spec.

Does the AT25P1024C1-10CI-1.8 support standard SPI modes, and which ones are validated?

Yes, the AT25P1024C1-10CI-1.8 explicitly supports SPI Modes 0 (CPOL = 0, CPHA = 0) and 3 (CPOL = 1, CPHA = 1), as confirmed in its official datasheet Features section. It does not support Modes 1 or 2. The device functions strictly as an SPI slave with dedicated SI and SO lines, requiring proper clock polarity and phase alignment from the host controller to ensure reliable command decoding and data transfer.

How does the HOLD pin function on the AT25P1024C1-10CI-1.8, and what timing constraints apply?

The HOLD pin on the AT25P1024C1-10CI-1.8 suspends ongoing serial communication without resetting the internal state. To activate HOLD, the pin must be driven low while SCK is low; to resume, it must be brought high while SCK remains low. During HOLD, SI inputs are ignored and SO enters high-impedance. Timing requirements include tHD (hold setup) ≥100 ns and tCD (hold hold time) ≥200 ns at 1.8 V, ensuring glitch-free suspension across all supported voltage ranges.

What write protection mechanisms does the AT25P1024C1-10CI-1.8 provide, and how are they configured?

The AT25P1024C1-10CI-1.8 provides dual-layer write protection: software-configurable block protection (BP0/BP1 bits in status register) for 1/4, 1/2, or full array lock, and hardware-based WP pin control enabled via WPEN bit. Protection is applied independently to memory and status register. Configuration requires WRSR instruction after WREN; WP pin effect depends on WPEN state - allowing flexible deployment from fully open to factory-locked configurations.

Is page write the only supported write method for the AT25P1024C1-10CI-1.8, and what happens if fewer than 128 bytes are written?

Yes, the AT25P1024C1-10CI-1.8 supports only 128-byte page writes - byte-wise or partial-page writes are not functional. If fewer than 128 bytes are clocked in after the WRITE instruction, the content of that page becomes undefined per datasheet specification. Writing more than 128 bytes causes address roll-over and overwrites earlier bytes in the same page. This architecture enforces atomic page updates, improving data consistency during power interruption.