Microchip Technology 25LC020AT-I/OT

Overview

25LC020AT-I/OT from Microchip Technology Inc. is a 2 Kbit (256 × 8) SPI Serial EEPROM with 16-byte page write capability, 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 serial communication, and block-level write protection (none/¼/½/all array). Used in embedded systems for storing calibration data, configuration settings, and firmware parameters.

For engineers reviewing the 25LC020AT-I/OT datasheet, 25LC020AT-I/OT pinout, 25LC020AT-I/OT application, or 25LC020AT-I/OT equivalent, key selection criteria include VCC range (2.5–5.5V), standby current (≤5 µA at +125°C), endurance (1 million erase/write cycles), data retention (>200 years), and compatibility with standard SPI Mode 0,0 and Mode 1,1 interfaces.

Technical Context

The 25LC020AT-I/OT implements a true SPI-compatible interface with separate SI (data in) and SO (data out) lines, CS-controlled selection, and SCK-synchronized transfers. It supports both byte and page write modes, with internal self-timed write cycles completing in ≤5 ms.

Its architecture includes a nonvolatile STATUS register with WIP, WEL, BP0, and BP1 bits for real-time write status monitoring and configurable block protection. The HOLD pin enables pausing of ongoing serial sequences without resetting state, allowing host microcontrollers to service higher-priority interrupts.

Key Specifications

Pinout & Package

25LC020AT-I/OT is packaged in 6-lead SOT-23 (OT suffix), a space-constrained surface-mount package measuring 2.9 mm × 1.6 mm × 1.1 mm with gull-wing leads. Pin 1 is marked by laser indentation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25AA020AT-I/OT and AT25020B-SSHL-T, the 25LC020AT-I/OT provides optimal balance of industrial temperature support, hardware write protection, and HOLD-based interrupt handling - making it the preferred choice for new designs requiring robust, interrupt-safe configuration storage.

Availability

25LC020AT-I/OT is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, and smart energy meter applications requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for 25LC020AT-I/OT 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 microcontroller, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 25LC020A family is designed specifically for reliable, low-power nonvolatile data storage in resource-constrained embedded systems - emphasizing SPI simplicity, industrial-grade reliability, and hardware-assisted data integrity.

FAQ

What is the maximum clock frequency supported by the 25LC020AT-I/OT?

The 25LC020AT-I/OT supports up to 10 MHz clock frequency when VCC is 4.5V to 5.5V. At 2.5V ≤ VCC < 4.5V, the maximum is 5 MHz, and at 1.8V ≤ VCC < 2.5V it is 3 MHz. These limits ensure timing compliance across voltage and temperature ranges. The 25LC020AT-I/OT datasheet specifies AC characteristics including setup/hold times referenced to these frequencies.

Does the 25LC020AT-I/OT require external pull-up resistors on its SO or WP pins?

No, the 25LC020AT-I/OT does not require external pull-ups on SO (it is actively driven and tri-stated) or WP (it has an internal weak pull-up when left unconnected, but Microchip recommends explicit routing to VCC or GND for deterministic behavior). The 25LC020AT-I/OT datasheet confirms WP is active-low and internally biased, though hardwiring is advised for safety-critical applications.

How does the HOLD function operate on the 25LC020AT-I/OT during an active SPI transaction?

The HOLD pin on the 25LC020AT-I/OT suspends serial communication mid-transaction when pulled low while SCK is low. SI, SO, and SCK enter high-impedance states, and the device retains internal state (address pointer, instruction phase). Resuming requires bringing HOLD high while SCK remains low. This behavior is fully documented in the 25LC020AT-I/OT functional description and timing diagrams.

Can the 25LC020AT-I/OT be used in automotive applications requiring AEC-Q100 qualification?

The 25LC020AT-I/OT is rated for Industrial temperature (–40°C to +85°C) and is not AEC-Q100 qualified. For automotive use, Microchip offers the 25LC020A-E/OT variant (E grade, –40°C to +125°C), which is AEC-Q100 Grade 3 qualified. The 25LC020AT-I/OT itself is intended for industrial and commercial systems, not under-hood automotive environments.

What happens to the write enable latch after a successful write operation on the 25LC020AT-I/OT?

After a successful byte, page, or STATUS register write, the write enable latch (WEL) in the 25LC020AT-I/OT is automatically reset to '0'. This prevents unintended subsequent writes and requires reissuing the WREN instruction before any further write attempt. This behavior is explicitly defined in the 25LC020AT-I/OT functional description and confirmed in the STATUS register documentation.