Microchip Technology 25AA160D-I/MS

Overview

25AA160D-I/MS from Microchip Technology is a 16 Kbit (2048 × 8) SPI Serial EEPROM with 32-byte page write capability, 1.8–5.5 V supply range, and Industrial temperature grade (−40°C to +85°C). It features hardware write protection via WP pin, HOLD suspend functionality, and self-timed 5 ms max write cycles - deployed in embedded control systems for parameter storage, calibration data retention, and firmware configuration.

For engineers reviewing the 25AA160D-I/MS datasheet, 25AA160D-I/MS pinout, 25AA160D-I/MS application, or 25AA160D-I/MS equivalent, key selection criteria include page size compatibility (32-byte), VCC operating margin (1.8 V min), HOLD/CS timing constraints, and block protection granularity (1/4, 1/2, or full array).

Technical Context

The 25AA160D-I/MS implements a standard SPI Mode 0,0 interface (CPOL = 0, CPHA = 0) with separate SI and SO lines, requiring CS assertion, SCK synchronization, and MSB-first data framing. Its internal architecture includes an 8-bit instruction register, page latches, and HV generator for EEPROM programming.

Write operations require explicit WREN instruction followed by CS high-to-low transition to initiate internal 5 ms erase/write cycle; STATUS register (WIP, WEL, BP0/BP1) enables real-time monitoring and configurable 1/4–100% array protection without external logic.

Key Specifications

Pinout & Package

25AA160D-I/MS is housed in an 8-lead MSOP (150 mil) package, measuring 3.0 mm × 3.0 mm × 1.1 mm, with gull-wing leads and Pb-free RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25AA160C-I/MS, the 25AA160D-I/MS delivers 100% more page-write throughput per transaction; versus AT25DF021-SSH-T, it provides dedicated hardware safety controls (WP/HOLD) essential for certified industrial firmware storage.

Availability

25AA160D-I/MS is available at Aetrix Electronics and suitable for smart metering, industrial PLC configuration, medical diagnostics, and automotive body control applications requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for 25AA160D-I/MS 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, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 25AA160D-I/MS belongs to Microchip's 25XX160 family of SPI Serial EEPROMs, engineered for robust, low-power, and pin-efficient nonvolatile storage in cost-sensitive industrial and consumer embedded systems.

FAQ

What is the maximum clock frequency supported by the 25AA160D-I/MS?

The 25AA160D-I/MS supports up to 10 MHz SPI clock frequency when VCC is 4.5 V to 5.5 V. At lower supply voltages (2.5 V ≤ VCC < 4.5 V), the maximum clock drops to 5 MHz; at 1.8 V ≤ VCC < 2.5 V, it is limited to 3 MHz. These limits ensure reliable setup/hold timing across voltage and temperature ranges - critical for deterministic communication in real-time control loops using the 25AA160D-I/MS.

How does the HOLD pin function during an active SPI transaction on the 25AA160D-I/MS?

The HOLD pin on the 25AA160D-I/MS suspends ongoing SPI communication without resetting the internal state. When asserted low while SCK is low, SI/SO/SCK inputs are ignored and SO enters high-impedance. The 25AA160D-I/MS resumes exactly where it left off upon HOLD release (high) - enabling host MCUs to service urgent interrupts while preserving EEPROM transaction integrity. This behavior is explicitly verified in DS22150B Figure 1-1.

What page size does the 25AA160D-I/MS use, and why does it matter for firmware design?

The 25AA160D-I/MS uses a 32-byte page size, double that of the 'C' variant. This directly impacts firmware efficiency: writing 32 bytes requires only one page-write command, whereas the 16-byte page version would need two. Crossing a 32-byte boundary causes wraparound - not overflow - so application code must validate address alignment before issuing WRITE commands to prevent unintended overwrites in the 25AA160D-I/MS.

Can the 25AA160D-I/MS be used in automotive applications requiring extended temperature operation?

The 25AA160D-I/MS is rated for Industrial temperature range (−40°C to +85°C), not Automotive (−40°C to +125°C). While its 'E' temp variants (e.g., 25AA160D-E/MS) meet AEC-Q100 Grade 3, the 'I' suffix explicitly denotes Industrial qualification. Using 25AA160D-I/MS in under-hood automotive environments risks parametric drift or failure outside its validated thermal envelope - always select the E-temp variant for such deployments.

How is write protection implemented on the 25AA160D-I/MS?

The 25AA160D-I/MS implements dual-layer write protection: software-based via STATUS register BP0/BP1 bits (configurable 0%, 25%, 50%, or 100% array lock), and hardware-based via WP pin combined with WPEN bit. When WP is low and WPEN = 1, nonvolatile STATUS register writes are blocked - preventing accidental corruption of protection settings. This layered scheme ensures firmware resilience even if software fails, making the 25AA160D-I/MS suitable for safety-critical parameter storage.