Microchip Technology 25AA160D-I/SN

Overview

25AA160D-I/SN 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 rating (−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 modules for parameter storage and firmware configuration.

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

Technical Context

The 25AA160D-I/SN implements a standard SPI Mode 0,0 interface with separate SI (data in) and SO (data out) lines, requiring CS assertion and SCK synchronization at up to 10 MHz (VCC ≥ 4.5 V). Its internal architecture includes a write-enable latch, STATUS register with WIP/WEL/BP bits, and HV generator for EEPROM cell programming.

Write operations are page-limited (32 bytes), constrained to physical page boundaries (0000h–001Fh, 0020h–003Fh, etc.), and require explicit WREN before WRITE. The HOLD pin suspends ongoing transfers without resetting the internal address pointer, enabling interrupt servicing on host microcontrollers.

Key Specifications

Pinout & Package

25AA160D-I/SN is packaged in an 8-lead SOIC (SN) with 150 mil width, RoHS-compliant matte tin finish, and JEDEC MS-012AC footprint. Pin 1 is CS (Chip Select), pin 4 is VSS (ground), and pin 8 is VCC (supply voltage).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25LC160D-I/SN and AT25160B-SSHL-T, the 25AA160D-I/SN uniquely supports 1.8 V operation and integrated hardware write protection - making it optimal for energy-sensitive and safety-critical designs where voltage margin and tamper resistance are primary concerns.

Availability

25AA160D-I/SN is available at Aetrix Electronics and suitable for industrial control systems, medical instrumentation, automotive body electronics, and smart metering applications requiring stable component supply across extended product lifecycles.

Supply support for 25AA160D-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, mixed-signal, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 25AA160D-I/SN belongs to Microchip's 25XX160 family of SPI Serial EEPROMs, engineered for robust nonvolatile data storage in cost-sensitive, space-constrained embedded systems with demanding reliability requirements.

FAQ

What is the minimum supply voltage required for reliable operation of the 25AA160D-I/SN?

The 25AA160D-I/SN operates reliably down to 1.8 V across its full industrial temperature range (−40°C to +85°C). Below this threshold, read/write functions are not guaranteed per Microchip DS22150B specifications. At 1.8 V, maximum clock frequency is reduced to 3 MHz, and write current drops to 3 mA - ensuring compatibility with energy-harvesting and coin-cell-powered systems. The 25AA160D-I/SN maintains full command set and timing compliance at 1.8 V.

How does the HOLD pin function during an active SPI read or write sequence in the 25AA160D-I/SN?

In the 25AA160D-I/SN, the HOLD pin suspends ongoing SPI communication when pulled low while SCK is low - placing SI, SO, and SCK into high-impedance states without resetting the internal address pointer or command state. Host MCU can service higher-priority interrupts and resume exactly where the transfer left off upon returning HOLD to high (with SCK still low). This behavior is fully defined in Figure 1-1 and Section 3.6 of DS22150B.

Can the 25AA160D-I/SN be used as a direct replacement for the 25AA160C-I/SN in an existing design?

No - the 25AA160D-I/SN is not a direct replacement for the 25AA160C-I/SN due to differing page sizes: 32 bytes vs. 16 bytes. Page write commands crossing a 16-byte boundary on the 'C' version behave differently than on the 'D' version, risking data corruption if firmware assumes 16-byte alignment. Software must be updated to enforce 32-byte page boundaries and validate address ranges before issuing WRITE instructions to the 25AA160D-I/SN.

What protection mechanisms prevent unintended writes to the 25AA160D-I/SN memory array?

The 25AA160D-I/SN employs four layered protections: (1) Power-on reset clears the write-enable latch; (2) WREN instruction must be issued and confirmed before any WRITE; (3) CS must go high after final data bit to trigger internal write cycle; (4) Hardware WP pin + WPEN bit blocks STATUS register writes when grounded. These are detailed in Sections 2.4, 2.7, and Table 2-4 of DS22150B - collectively preventing corruption from noise, brown-out, or software errors.

Does the 25AA160D-I/SN support SPI Mode 1,1 or only Mode 0,0?

The 25AA160D-I/SN supports SPI Mode 0,0 exclusively - sampling SI on the rising edge of SCK and updating SO on the falling edge, with CPOL = 0 and CPHA = 0. It does not support Mode 1,1 (CPOL = 1, CPHA = 1) or other variants. This is confirmed in Section 2.1 ("Principles of Operation") and Figure 1-2/1-3 timing diagrams of DS22150B. Host MCU SPI peripheral must be configured accordingly.