Microchip Technology 25LC020A-I/SN

Overview

25LC020A-I/SN 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 pauses, and block-level write protection (none/¼/½/all array). Used in embedded system configuration storage, sensor calibration data retention, and firmware parameter backup.

For engineers reviewing the 25LC020A-I/SN datasheet, 25LC020A-I/SN pinout, 25LC020A-I/SN application, or 25LC020A-I/SN equivalent, key selection considerations include VCC range (2.5–5.5V), SO high-impedance tri-state behavior during HOLD/CS high, self-timed 5 ms max write cycle, 1 M endurance cycles, and compatibility with standard SPI Mode 0,0 and Mode 1,1 interfaces.

Technical Context

The 25LC020A-I/SN implements a true SPI-compatible interface with separate SI (data in) and SO (data out) lines, CS-controlled device selection, and SCK-synchronized transfers. It supports both byte and page write modes, with automatic address incrementing during sequential reads and wraparound at 0xFF.

Its internal architecture includes a write enable latch (WEL), STATUS register with WIP/WEL/BP0/BP1 bits, and hardware-based write protection via WP pin and BP bits. The HOLD pin suspends ongoing SPI communication without resetting the sequence, enabling host MCU interrupt servicing while preserving transaction state.

Key Specifications

Pinout & Package

25LC020A-I/SN is packaged in an 8-lead SOIC (SN) with 150 mil width. Pin functions are electrically identical across SOIC, PDIP, MSOP, TSSOP, DFN, and SOT-23 variants per datasheet Table 3-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25AA020A-I/SN and AT25020B-SSHL-T, the 25LC020A-I/SN offers optimal balance of voltage flexibility, HOLD functionality, and Microchip's robust qualification for industrial use - making it the preferred choice for real-time embedded systems requiring deterministic SPI control and long-term reliability.

Availability

25LC020A-I/SN is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, and smart metering applications requiring stable component supply, extended temperature operation, and long-lifecycle support.

Supply support for 25LC020A-I/SN 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 belongs to Microchip's serial EEPROM product line, engineered for reliable, low-power nonvolatile data storage in resource-constrained embedded systems where SPI interface simplicity and industrial-grade endurance are critical.

FAQ

What is the maximum clock frequency supported by the 25LC020A-I/SN?

The 25LC020A-I/SN 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; below 2.5V, it drops to 3 MHz. These limits ensure reliable setup/hold timing across voltage and temperature ranges - critical for deterministic SPI communication in industrial designs using the 25LC020A-I/SN.

Does the 25LC020A-I/SN require external pull-up resistors on its SO or SI lines?

No, the 25LC020A-I/SN does not require external pull-ups on SO or SI. SO is actively driven or tri-stated; SI is CMOS input with leakage <±1 µA. Pull-ups may interfere with SPI timing or cause contention. Only CS, WP, and HOLD should be pulled high if left floating in system design - confirmed in DS21833G Section 1.0 DC Characteristics and Pin Descriptions for the 25LC020A-I/SN.

How does the HOLD pin function during an active SPI transaction with the 25LC020A-I/SN?

The HOLD pin pauses SPI communication mid-transaction: when pulled low while SCK is low, SI/SO/SCK inputs are ignored and SO enters high-impedance. The 25LC020A-I/SN retains internal state (address pointer, instruction phase) and resumes exactly where paused upon HOLD returning high. This enables MCU interrupt servicing without retransmission - a key feature documented in Section 2.8 and Figure 1-1 of the 25LC020A-I/SN datasheet.

Can the 25LC020A-I/SN be used in automotive applications?

The 25LC020A-I/SN is rated for Industrial temperature (–40°C to +85°C), not Automotive (–40°C to +125°C). Microchip offers the 25LC020A-E/SN variant for automotive use. Using the -I/SN version outside its specified range risks timing violations, increased write failure rate, or data retention loss - so the 25LC020A-I/SN is unsuitable for under-hood or dashboard modules requiring AEC-Q100 compliance.

What happens if a page write crosses a 16-byte boundary on the 25LC020A-I/SN?

If a page write command attempts to cross a 16-byte boundary (e.g., writing 10 bytes starting at address 0x0F), the 25LC020A-I/SN wraps data back to the start of the same page (0x00), overwriting prior bytes. This behavior is explicitly defined in Section 2.3 and Note on DS21833G-page 6. Firmware must enforce page-aligned writes - a critical constraint when implementing configuration storage using the 25LC020A-I/SN.