Microchip Technology 25AA160-I/SN

Overview

25AA160-I/SN from Microchip Technology is a 16 Kbit (2048 × 8) SPI-compatible serial EEPROM with industrial temperature range (−40°C to +85°C), 1.8–5.5 V supply voltage, and 1 MHz max clock frequency. It features hardware write protection via WP pin, HOLD functionality for interrupt-safe pausing, and 16-byte page write capability. It is used in embedded systems for nonvolatile storage of configuration data, calibration parameters, and firmware patches.

For engineers reviewing the 25AA160-I/SN datasheet, 25AA160-I/SN pinout, 25AA160-I/SN application, or 25AA160-I/SN equivalent, key selection considerations include its 1.8 V minimum operating voltage, 5 ms max internal write cycle time, block-level write protection (0/¼/½/all array), and SOIC-8 (SN) package compatibility with space-constrained PCB layouts.

Technical Context

The 25AA160-I/SN implements a standard SPI Mode 0,0 or Mode 1,1 interface with separate SI (data in) and SO (data out) lines, CS-controlled selection, and SCK-synchronized transfers. Its internal architecture includes a status register with WIP, WEL, BP0/BP1, and WPEN bits, enabling real-time write-in-progress monitoring and configurable memory segmentation.

It supports sequential read with automatic address rollover, byte/page write with on-chip self-timed erase-and-write cycles, and hardware-based data protection including power-on reset of the write enable latch, built-in write-protect logic, and ESD tolerance >4 kV. All operations require explicit WREN instruction before WRITE or WRSR commands.

Key Specifications

Pinout & Package

25AA160-I/SN is housed in an 8-pin SOIC (SN) package, 150 mil body width, JEDEC MS-012 compliant, with gull-wing leads and 1.27 mm pitch. The package is RoHS-compliant and suitable for reflow soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25AA160A-I/SN, the 25AA160-I/SN lacks the latest ESD enhancements and is marked "Not recommended for new designs"; compared with 25LC160-I/SN, it supports lower voltage operation but trades off maximum clock speed - making it optimal for cost-sensitive, low-power industrial nodes where 1 MHz bandwidth suffices.

Availability

25AA160-I/SN is available at Aetrix Electronics and suitable for industrial sensor calibration, smart meter firmware storage, medical device settings backup, and automotive body control module applications requiring stable component supply and long-term obsolescence management.

Supply support for 25AA160-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, serving industrial, automotive, consumer, and communications markets with vertically integrated silicon and development tools.

The 25AA160-I/SN belongs to Microchip's legacy SPI Serial EEPROM product line, designed specifically for reliable, low-voltage, low-pin-count nonvolatile storage in resource-constrained embedded systems where simplicity, longevity, and proven qualification matter more than raw speed.

FAQ

What is the minimum supply voltage required for reliable operation of the 25AA160-I/SN?

The 25AA160-I/SN operates reliably down to 1.8 V across its full industrial temperature range (−40°C to +85°C). This is confirmed in the DC Characteristics table (Param D1–D4) and Device Selection Table, where 25AA160 is explicitly rated for 1.8–5.5 V. At 1.8 V, AC timing parameters such as clock high/low time increase to 475 ns, and max clock frequency reduces to 1 MHz - all fully supported without derating or external circuitry. The 25AA160-I/SN is therefore suitable for direct connection to 1.8 V MCUs without level shifting.

Does the 25AA160-I/SN support page write, and what is the page size?

Yes, the 25AA160-I/SN supports page write with a fixed page size of 16 bytes. As stated in the Features section and Functional Description (Section 3.3), up to 16 bytes can be loaded into the page latches before initiating an internal write cycle, provided all addresses reside within the same page boundary (e.g., 0x0000–0x000F). Exceeding the page boundary causes wraparound and potential data corruption. This capability reduces total write cycles by up to 16× versus byte-write mode, directly extending effective endurance in high-update-rate applications.

How does the HOLD pin function during an active SPI transaction on the 25AA160-I/SN?

The HOLD pin on the 25AA160-I/SN suspends ongoing SPI communication without resetting internal state. When pulled low while SCK is low, it places SI, SCK, and SO into high-impedance and ignores further input transitions - allowing the host MCU to service interrupts. To resume, HOLD must be raised while SCK remains low; then communication continues from the exact bit position where it paused. This behavior is detailed in Section 2.6 and Figure 1-1, and is critical for deterministic real-time systems where SPI transfers cannot be aborted and restarted.

Can the 25AA160-I/SN be used in place of the 25LC160-I/SN, and what are the key trade-offs?

The 25AA160-I/SN and 25LC160-I/SN share identical pinout, instruction set, memory map, and package (SOIC-8), but differ in voltage and speed: 25AA160-I/SN supports 1.8–5.5 V and 1 MHz max, while 25LC160-I/SN requires 2.5–5.5 V and supports 2 MHz. Substituting 25AA160-I/SN into a 25LC160-I/SN design works if VCC ≥2.5 V and clock ≤1 MHz; however, using 25LC160-I/SN in a 1.8 V system will fail. Firmware remains compatible, but timing margins and power consumption differ - verify AC specs under actual operating conditions.

What write protection mechanisms does the 25AA160-I/SN provide, and how are they configured?

The 25AA160-I/SN provides dual-layer write protection: (1) software-controlled via BP0/BP1 bits in the Status Register (set by WRSR instruction) to protect 0%, 25%, 50%, or 100% of memory; and (2) hardware-controlled via WP pin + WPEN bit - when WPEN=1 and WP=low, writes to nonvolatile Status Register bits are blocked. Configuration is persistent across power cycles. These mechanisms are documented in Sections 3.5, 3.6, and Table 3-2, enabling secure storage of calibration constants or cryptographic keys without risk of accidental overwrite.