Microchip Technology 25LC160B-I/ST

Overview

25LC160B-I/ST from Microchip Technology Inc. is a 16 Kbit (2048 × 8) SPI-compatible serial EEPROM with 32-byte page write capability, 10 MHz max clock frequency, and industrial temperature range (–40°C to +85°C). It operates from 2.5V to 5.5V, features hardware write protection via WP pin and STATUS register, and is used for nonvolatile parameter storage in microcontroller-based embedded systems.

For engineers reviewing the 25LC160B-I/ST datasheet, 25LC160B-I/ST pinout, 25LC160B-I/ST application, or 25LC160B-I/ST equivalent, this page delivers verified electrical specs, validated SPI timing behavior, confirmed package mapping to TSSOP-8, and real-world use context for firmware configuration, calibration data retention, and boot-time parameter loading.

Technical Context

The 25LC160B-I/ST implements a standard SPI Mode 0,0 interface with separate SI (data-in) and SO (data-out) lines, requiring CS low and HOLD high for normal operation. Its internal architecture includes an 8-bit instruction register, page latches, and high-voltage generator for EEPROM programming.

It supports sequential read with automatic address increment, byte/page write with self-timed 5 ms internal write cycle, and configurable block protection (none, 1/4, 1/2, or full array) via BP0/BP1 bits in the STATUS register. Write enable latch (WEL) must be set via WREN instruction prior to any write operation.

Key Specifications

Pinout & Package

25LC160B-I/ST is packaged in an 8-lead TSSOP (Thin Shrink Small Outline Package), Pb-free and RoHS compliant, with 0.65 mm lead pitch and body dimensions of 3.0 mm × 4.4 mm × 1.2 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25LC160B-I/SN, the 25LC160B-I/ST offers superior board-area efficiency and thermal performance in space-constrained designs; versus AT25160B-SSHL-T, it provides guaranteed HOLD support and tighter timing compliance across full voltage range-critical for deterministic real-time systems.

Availability

25LC160B-I/ST is available at Aetrix Electronics and suitable for industrial sensor nodes, medical device calibration storage, and automotive body control modules requiring stable component supply, long-life data retention, and SPI-compatible nonvolatile memory.

Supply support for 25LC160B-I/ST 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 microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 25LC160B-I/ST belongs to Microchip's 25XX160A/B serial EEPROM product line, designed specifically for robust, low-power, SPI-based configuration and calibration data storage in industrial, automotive, and medical applications.

FAQ

What is the maximum clock frequency supported by the 25LC160B-I/ST?

The 25LC160B-I/ST supports up to 10 MHz SPI clock frequency when VCC is 4.5V to 5.5V. At 2.5V ≤ VCC < 4.5V, the maximum clock drops to 5 MHz, and at 1.8V ≤ VCC < 2.5V, it is limited to 3 MHz. These limits are defined in Table 1-2 of the DS21807D datasheet and ensure reliable setup/hold timing across voltage and temperature ranges. The 25LC160B-I/ST must operate within these constraints to avoid read/write corruption.

Does the 25LC160B-I/ST support page write operations, and what is the page size?

Yes, the 25LC160B-I/ST supports page write operations with a fixed 32-byte page size, distinguishing it from the 'A' version (16-byte pages). This allows up to 32 bytes to be loaded into the page buffer before initiating the internal 5 ms write cycle. Page boundaries align to integer multiples of 32 (e.g., 0x000–0x01F, 0x020–0x03F), and crossing boundaries causes wraparound-so the 25LC160B-I/ST requires firmware-level boundary checking.

How does hardware write protection work on the 25LC160B-I/ST?

Hardware write protection on the 25LC160B-I/ST requires both the WP pin (Pin 3) to be low AND the WPEN bit (bit 7 of STATUS register) to be set high. When active, it disables writes to nonvolatile STATUS bits (BP0, BP1, WPEN) but permits normal memory reads and writes. If WP is high or WPEN is low, hardware protection is disabled. This dual-condition mechanism prevents accidental lockout during power-up or firmware errors.

What is the purpose of the HOLD pin on the 25LC160B-I/ST, and how is it used?

The HOLD pin (Pin 7) suspends an ongoing SPI transaction without resetting internal state, allowing the host MCU to service higher-priority interrupts and resume exactly where it left off. To activate HOLD, the pin must be pulled low while SCK is low; resuming requires bringing HOLD high while SCK remains low. During HOLD, SI, SCK, and SO enter high-impedance states, and only CS retains functional control-this behavior is fully specified in Figure 1-1 and Section 2.1 of the 25LC160B-I/ST datasheet.

What temperature range and packaging does the 25LC160B-I/ST support?

The 25LC160B-I/ST is rated for the industrial temperature range of –40°C to +85°C and is supplied in an 8-lead TSSOP package (ST suffix), with Pb-free matte tin finish, 0.65 mm lead pitch, and JEDEC-standard footprint. This package is distinct from PDIP (P), SOIC (SN), and MSOP (MS) variants-each with unique mechanical dimensions and thermal characteristics. The 25LC160B-I/ST's TSSOP variant optimizes board area and thermal dissipation for high-density layouts.