Microchip Technology 25LC1024T-E/SM

Overview

25LC1024T-E/SM from Microchip Technology Inc. is a 1-Mbit (131,072-byte) SPI serial EEPROM with byte/page write, 256-byte page size, 20 MHz max clock speed at 4.5–5.5V, and deep power-down current of 1 µA at 2.5V. It supports industrial and extended temperature ranges (−40°C to +125°C) and is AEC-Q100 qualified for automotive use.

For engineers reviewing the 25LC1024T-E/SM datasheet, 25LC1024T-E/SM pinout, 25LC1024T-E/SM application, or 25LC1024T-E/SM equivalent, key selection criteria include SPI interface timing compliance (e.g., TCSS ≤ 50 ns at 2.5V), sector-level hardware write protection (BP0/BP1 bits), HOLD pin suspend functionality, and 1M endurance cycles with >200-year data retention.

Technical Context

The 25LC1024T-E/SM implements a standard SPI Mode 0,0/Modes 1,1 interface with separate SI/SO lines, CS-controlled selection, and HOLD-enabled transaction suspension. Its internal architecture includes an 8-bit instruction register, page latches, and HV generator for EEPROM programming.

It supports four erase granularities-byte, page (6 ms), sector (10 ms), and chip (10 ms)-without requiring pre-erase for writes. Write protection is enforced via nonvolatile BP0/BP1 bits in the STATUS register and hardware WP pin logic gated by WPEN bit.

Key Specifications

Pinout & Package

25LC1024T-E/SM uses an 8-lead SOIJ (Small Outline Integrated Circuit, J-bend) package with 1.27 mm pitch, RoHS-compliant matte tin finish, and exposed pad electrically isolated per Microchip's DFN-S note (not applicable to SOIJ).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25DF041A-SSH-T and BR25H128FJ-WE2, the 25LC1024T-E/SM uniquely balances 1-Mbit density, 1 µA deep power-down, HOLD suspend, and AEC-Q100 qualification - making it optimal for automotive and industrial edge devices requiring robust, low-power, interrupt-tolerant nonvolatile storage.

Availability

25LC1024T-E/SM is available at Aetrix Electronics and suitable for automotive telematics, industrial PLC configuration, medical device calibration, smart meter firmware patching, and battery-powered sensor node applications requiring stable component supply across extended temperature and long product lifecycles.

Supply support for 25LC1024T-E/SM 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 solutions, with global manufacturing and quality certifications including ISO/TS 16949 and AEC-Q200.

The 25LC1024T-E/SM belongs to Microchip's serial EEPROM product line designed for reliable, low-power, SPI-based nonvolatile storage in automotive, industrial, and medical systems where data integrity and long-term retention are critical.

FAQ

What is the maximum SPI clock frequency supported by the 25LC1024T-E/SM?

The 25LC1024T-E/SM supports up to 20 MHz SPI clock frequency when VCC is 4.5V–5.5V and ambient temperature is within the Industrial or Extended range. At lower supply voltages (2.5V ≤ VCC < 4.5V), the maximum clock frequency is reduced to 10 MHz to maintain timing margin and signal integrity - verified per Table 1-2 AC Characteristics in DS20002064E.

Does the 25LC1024T-E/SM support hardware write protection independent of software configuration?

Yes, the 25LC1024T-E/SM supports hardware write protection via the WP pin, but only when the WPEN bit in the STATUS register is set to '1'. When WP is low and WPEN = 1, writes to nonvolatile STATUS bits (BP0, BP1, WPEN) are blocked - however, array writes remain enabled unless BP0/BP1 are also set. This dual-layer protection is documented in Section 2.3 and Table 3-4 of DS20002064E.

How does the HOLD pin function during an active SPI transaction on the 25LC1024T-E/SM?

The HOLD pin on the 25LC1024T-E/SM suspends an ongoing SPI sequence without resetting internal state: SO immediately goes high-Z, and SI/SCK transitions are ignored until HOLD is returned high while SCK is low. The device resumes exactly where it left off - confirmed by Figure 1-1 timing diagram and Section 2.6 functional description in DS20002064E.

What is the page size and maximum write length per transaction for the 25LC1024T-E/SM?

The 25LC1024T-E/SM has a fixed 256-byte page size, and up to 256 bytes can be written in a single page-write transaction - provided all addresses fall within the same physical page boundary (e.g., 0x0000–0x00FF). Crossing a page boundary causes wraparound within the current page, as explicitly warned in Figure 3-3 notes and Section 3.3 of DS20002064E.

Is the 25LC1024T-E/SM compatible with standard SPI Mode 0,0 and Mode 1,1 configurations?

Yes, the 25LC1024T-E/SM is fully compatible with both SPI Mode 0,0 (CPOL = 0, CPHA = 0) and Mode 1,1 (CPOL = 1, CPHA = 1), as shown in Figure 1-2 and Figure 1-3 timing diagrams. Data is sampled on SCK rising edge (SI) and output on SCK falling edge (SO), with CS active-low framing - consistent with standard microcontroller SPI peripherals including PIC® and ARM Cortex-M families.