Microchip Technology 25LC320AT-E/MNY

Overview

25LC320AT-E/MNY from Microchip Technology Inc. is a 32-Kbit SPI Serial EEPROM with 4096 × 8-bit organization, 32-byte page size, and AEC-Q100 qualified Extended temperature range (–40°C to +125°C). It operates at up to 10 MHz clock frequency with self-timed 5 ms write cycles and hardware write protection via WP pin and STATUS register. It is used in automotive body control modules for storing calibration data and fault logs.

For engineers reviewing the 25LC320AT-E/MNY datasheet, 25LC320AT-E/MNY pinout, 25LC320AT-E/MNY application, or 25LC320AT-E/MNY equivalent, key selection criteria include SPI timing compliance at 125°C, block write-protection granularity (1/4, 1/2, or full array), endurance (>1M cycles), data retention (>200 years), and TDFN-8 package thermal performance in constrained automotive PCB layouts.

Technical Context

The 25LC320AT-E/MNY implements a standard SPI Mode 0,0 interface with separate SI and SO lines, CS-controlled selection, and HOLD pin for transaction suspension without reset. Its internal architecture includes an 8-bit instruction register, page latches, and HV generator for EEPROM programming.

It supports four block protection configurations via BP0/BP1 bits in the nonvolatile STATUS register, and hardware write protection is enabled only when both WPEN = 1 and WP = low. The device powers on with WEL reset and SO in high-impedance state, requiring explicit WREN before any WRITE sequence.

Key Specifications

Pinout & Package

25LC320AT-E/MNY is packaged in an 8-lead TDFN (2 mm × 3 mm, 0.5 mm pitch) with exposed pad (optional VSS connection). Pin numbering follows standard TDFN orientation: pin 1 = CS, pin 2 = SO, pin 3 = WP, pin 4 = VSS, pin 5 = SI, pin 6 = SCK, pin 7 = HOLD, pin 8 = VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25LC320AT-E/MNY, the 25AA320AT-I/MNY offers broader voltage compatibility but lacks automotive qualification, while the AT25DF321A-SHB-T delivers higher bandwidth and density at the cost of SPI protocol complexity and layout redesign.

Availability

25LC320AT-E/MNY is available at Aetrix Electronics and suitable for automotive electronics, industrial control systems, and medical device manufacturing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 25LC320AT-E/MNY 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 25LC320A family is designed specifically for automotive and industrial applications demanding high-reliability nonvolatile storage with AEC-Q100 qualification, robust SPI timing, and flexible hardware write protection.

FAQ

What is the maximum clock frequency supported by the 25LC320AT-E/MNY across its full operating voltage and temperature range?

The 25LC320AT-E/MNY supports up to 10 MHz at VCC ≥ 4.5V and TA = –40°C to +125°C. At 2.5V ≤ VCC < 4.5V, maximum clock frequency is 5 MHz; at 1.8V ≤ VCC < 2.5V (not applicable to 25LC320AT-E/MNY due to its 2.5V min VCC spec), it would be 3 MHz. All AC timing parameters in DS20001828H are validated for the Extended temperature grade.

Does the 25LC320AT-E/MNY require external pull-up resistors on its SI, SO, or HOLD pins?

The 25LC320AT-E/MNY does not require external pull-ups on SI or HOLD - these inputs have internal weak pull-downs. However, SO is an open-drain–like output that enters high-impedance when deselected or during HOLD; a 4.7 kΩ external pull-up to VCC is recommended for reliable signal integrity on shared SPI buses, especially in noisy automotive environments.

How does the HOLD function behave if asserted while SCK is high?

If HOLD is pulled low while SCK is high, the 25LC320AT-E/MNY will not enter HOLD mode until the next SCK high-to-low transition. This behavior is explicitly defined in Section 2.6 of DS20001828H. To ensure deterministic pause, HOLD must be asserted only when SCK is low - otherwise, one additional clock edge may be processed before suspension.

Can the 25LC320AT-E/MNY be used in a system where the WP pin is permanently grounded?

Yes - the 25LC320AT-E/MNY supports WP pin grounding when WPEN = 0 in the STATUS register. In this configuration, hardware write protection is disabled, allowing full read/write access to both memory array and STATUS register. WPEN can be set later via WRSR to enable hardware lock, providing flexible factory vs. field programming workflows.

What is the purpose of the exposed pad on the 25LC320AT-E/MNY TDFN package?

The exposed pad on the 25LC320AT-E/MNY TDFN package is electrically connected to VSS and serves dual purposes: thermal dissipation (reducing junction temperature rise during write cycles) and mechanical stability (improving solder joint reliability). Microchip recommends connecting it to the PCB ground plane using ≥4 thermal vias for optimal performance in automotive under-hood applications.