Microchip Technology 25AA160A-I/MS

Overview

25AA160A-I/MS from Microchip Technology Inc. is a 16 Kbit (2048 × 8) SPI serial EEPROM with 1.8–5.5 V supply range, 16-byte page size, and industrial temperature rating (–40°C to +85°C). It features hardware write protection via WP pin and STATUS register, HOLD functionality for bus arbitration, and self-timed 5 ms max write cycles. Used in embedded systems for firmware parameter storage, calibration data retention, and configuration backup.

For engineers reviewing the 25AA160A-I/MS datasheet, 25AA160A-I/MS pinout, 25AA160A-I/MS application, or 25AA160A-I/MS equivalent, key selection criteria include V_CC compatibility down to 1.8 V, page-write boundary handling, WPEN/WP interaction, and MSOP-8 package footprint constraints in space-constrained PCB layouts.

Technical Context

The 25AA160A-I/MS implements a standard SPI Mode 0,0 interface with separate SI/SO lines, CS-controlled selection, and HOLD-driven pause capability. Its internal architecture includes an 8-bit instruction register, page latches, HV generator for EEPROM programming, and status register with WIP, WEL, BP0/BP1, and WPEN bits.

Write operations require explicit WREN instruction followed by CS high-to-low transition to initiate internal 5 ms erase/write cycle; reads support sequential addressing with automatic address rollover at 07FFh. Block protection configures write lock on none, upper 1/4, upper 1/2, or full array via nonvolatile BP bits.

Key Specifications

Pinout & Package

25AA160A-I/MS is housed in an 8-lead MSOP (Mini Small Outline Package), 3.0 mm × 4.9 mm body, 0.65 mm lead pitch, RoHS-compliant matte tin finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25AA160A-I/MS, 25LC160A-I/MS excludes 1.8 V operation but maintains full functional equivalence above 2.5 V, while AT25160B-MAHL-T sacrifices HOLD and hardware WP for Atmel ecosystem alignment-neither offers pin-to-pin replacement without board-level review.

Availability

25AA160A-I/MS is available at Aetrix Electronics and suitable for industrial sensor nodes, medical device calibration, automotive body control modules, and smart home gateways requiring stable component supply across extended product lifecycles.

Supply support for 25AA160A-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 25AA160A-I/MS belongs to Microchip's serial EEPROM product line, engineered for reliable nonvolatile data storage in resource-constrained embedded systems where SPI interface simplicity, low voltage operation, and long-term data integrity are critical.

FAQ

What is the maximum clock frequency supported by the 25AA160A-I/MS across its full voltage range?

The 25AA160A-I/MS supports up to 10 MHz at V_CC ≥ 4.5 V, 5 MHz at 2.5 V ≤ V_CC < 4.5 V, and 3 MHz at 1.8 V ≤ V_CC < 2.5 V. These AC timing limits are defined in Table 1-2 of DS21807D and directly impact achievable read throughput and command latency in the 25AA160A-I/MS.

How does the 25AA160A-I/MS handle page write operations that cross physical page boundaries?

The 25AA160A-I/MS wraps page write data back to the start of the current 16-byte page if a write crosses the boundary - it does not auto-advance to the next page. This behavior is explicitly documented in Section 2.3 and requires application firmware to enforce page-aligned writes or split multi-page transfers manually for the 25AA160A-I/MS.

Can the 25AA160A-I/MS be used in systems powered by a 1.8 V supply rail?

Yes, the 25AA160A-I/MS is fully specified for 1.8–5.5 V operation per the Device Selection Table and DC Characteristics (D011–D013). It delivers guaranteed 3 MHz SPI clocking, <1 µA standby current, and full read/write functionality at 1.8 V - a key differentiator from the 25LC160A-I/MS variant, which requires ≥2.5 V.

What is the role of the HOLD pin on the 25AA160A-I/MS, and how must it be used correctly?

The HOLD pin on the 25AA160A-I/MS pauses ongoing SPI communication without resetting the sequence. To activate, HOLD must be pulled low while SCK is low; to resume, it must be raised while SCK remains low. Misuse (e.g., toggling HOLD during SCK high) causes undefined behavior, as detailed in Figure 1-1 and Section 3.6 of the 25AA160A-I/MS datasheet.

How is write protection implemented on the 25AA160A-I/MS, and what combinations provide full array lock?

The 25AA160A-I/MS implements dual-layer write protection: hardware via WP pin (enabled only when WPEN=1 in STATUS register) and software via BP0/BP1 bits. Full array protection (0000h–07FFh) is achieved when BP1=1 and BP0=1, as defined in Table 2-3. The WP pin has no effect unless WPEN is set, allowing safe installation in systems with grounded WP lines.