Microchip Technology 25AA160BT-I/ST

Overview

25AA160BT-I/ST 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, HOLD functionality for bus arbitration, and self-timed 5 ms max write cycles. Used in microcontroller-based systems for parameter storage, calibration data retention, and firmware configuration in industrial control modules.

For engineers reviewing the 25AA160BT-I/ST datasheet, 25AA160BT-I/ST pinout, 25AA160BT-I/ST application, or 25AA160BT-I/ST equivalent, key selection criteria include VCC operating range (1.8–5.5 V), page size (16 bytes), SPI clock support up to 10 MHz at 4.5–5.5 V, and TSSOP-8 package compatibility with space-constrained PCB layouts.

Technical Context

The 25AA160BT-I/ST implements a standard SPI Mode 0,0 interface with separate SI (data in) and SO (data out) lines, requiring CS, SCK, and optional HOLD/WP signals. Its internal architecture includes an 8-bit instruction register, page latches, and high-voltage generation circuitry 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 block protection of upper 1/4, 1/2, or full memory array.

Key Specifications

Pinout & Package

25AA160BT-I/ST is housed in an 8-lead TSSOP (Thin Shrink Small Outline Package) with 0.65 mm lead pitch, optimized for automated assembly and compact board layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 25AA160AT-I/ST, the 25AA160BT-I/ST adds essential HOLD functionality for interrupt-safe SPI communication; versus AT25160B-SSHL-T, it delivers superior ESD immunity, deterministic write-protection logic, and native Microchip ecosystem compatibility.

Availability

25AA160BT-I/ST is available at Aetrix Electronics and suitable for industrial control systems, medical instrumentation, smart energy meters, and automotive body electronics requiring stable component supply, long-term obsolescence management, and RoHS-compliant sourcing.

Supply support for 25AA160BT-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 microcontroller, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 25AA160BT-I/ST belongs to Microchip's 25XX160A/B family of SPI Serial EEPROMs, designed specifically for reliable, low-power, pin-efficient nonvolatile storage in cost-sensitive embedded systems with stringent longevity and environmental requirements.

FAQ

What is the maximum SPI clock frequency supported by the 25AA160BT-I/ST?

The 25AA160BT-I/ST supports up to 10 MHz SPI clock frequency when VCC is 4.5–5.5 V. At 2.5–4.5 V, max clock drops to 5 MHz, and at 1.8–2.5 V, it is limited to 3 MHz. These values are specified in Table 1-2 AC Characteristics and directly impact read/write throughput in host MCU implementations.

Does the 25AA160BT-I/ST require external pull-up resistors on its SPI lines?

No external pull-ups are required on SI, SO, or SCK for normal operation - all are actively driven. However, CS, WP, and HOLD should be pulled up externally (typically 10 kΩ to VCC) to ensure defined logic states during power-up and idle periods, preventing unintended device activation or write protection disablement.

How does the HOLD function operate in the 25AA160BT-I/ST during an active SPI transaction?

The HOLD pin pauses ongoing SPI communication when asserted low during SCK low time; SI, SCK, and SO enter high-impedance state, and the internal state machine retains position. Resuming requires HOLD high while SCK remains low. This allows the host MCU to service higher-priority interrupts without losing transaction context - a feature confirmed in Section 3.6 of DS21807D.

Can the 25AA160BT-I/ST be used in a 1.8 V system without level shifters?

Yes - the 25AA160BT-I/ST is fully specified for 1.8 V operation, including DC characteristics (VIH1/VIL1 thresholds), AC timing (e.g., 3 MHz max clock), and functional behavior. Its 1.8–5.5 V VCC range eliminates need for voltage translation when interfacing with 1.8 V MCUs or FPGAs, as verified in Table 1-1 and Table 1-2 of the datasheet.

What memory protection mechanisms are implemented in the 25AA160BT-I/ST?

The 25AA160BT-I/ST provides three-tier protection: (1) Software-controlled block protection (BP0/BP1 bits) for upper 1/4, 1/2, or full array; (2) Hardware write protection via WP pin enabled by WPEN bit; (3) Power-on reset of write enable latch. All are documented in Sections 2.5–2.6 and Table 2-3 of DS21807D, ensuring robust defense against accidental or malicious writes.