Microchip Technology AT25128A-10PU-1.8

Overview

AT25128A-10PU-1.8 from Microchip Technology (formerly Atmel) is a 128 Kbit SPI serial EEPROM organized as 16,384 × 8 bits, operating from 1.8 V to 5.5 V, supporting 20 MHz clock rate at 5 V, and featuring 64-byte page write, hardware/software write protection, and industrial temperature range (−40°C to +85°C). It serves as nonvolatile data storage in microcontroller-based embedded systems requiring low-voltage operation and robust data retention.

For engineers reviewing the AT25128A-10PU-1.8 datasheet, AT25128A-10PU-1.8 pinout, AT25128A-10PU-1.8 application, or AT25128A-10PU-1.8 equivalent, key selection considerations include its 1.8 V–5.5 V supply range, SPI Mode 0/3 compatibility, 5 ms max self-timed write cycle, block write protection (1/4, 1/2, or full array), and 8-lead PDIP package with RoHS-compliant lead-free/halogen-free construction.

Technical Context

The AT25128A-10PU-1.8 implements a synchronous serial peripheral interface (SPI) as a slave device with separate SI (input) and SO (output) pins, supporting MSB-first transmission and op-code–driven command execution (e.g., WREN, READ, WRITE, RDSR). Its instruction register accepts 8-bit op-codes followed by address and data bytes, with CS falling edge initiating each transaction.

It integrates nonvolatile status register bits (WPEN, BP1/BP0, WEN, RDY) controlling hardware write protection via WP pin, programmable block protection levels, and ready/busy status reporting. Internal write cycles are fully self-timed (≤5 ms), require no pre-erase, and suspend all commands except RDSR until completion.

Key Specifications

Pinout & Package

AT25128A-10PU-1.8 is housed in an 8-lead Plastic Dual In-line Package (PDIP), 0.300" wide body, RoHS-compliant and halogen-free per ordering code suffix "U".

Key Features

Applications

Equivalent & Alternatives

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

Compared with M95128-WMN6TP and BR24G128FJ-WE2, the AT25128A-10PU-1.8 uniquely combines 1.8 V–5.5 V operation, HOLD pin support, 8-lead PDIP packaging, and hardware-enforced block protection - making it optimal for industrial prototyping, legacy-compatible upgrades, and systems requiring interrupt-safe SPI communication.

Availability

AT25128A-10PU-1.8 is available at Aetrix Electronics and suitable for industrial PLC I/O modules, medical sensor calibration storage, smart energy meter firmware logging, and automotive body control unit settings requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant through-hole assembly.

Supply support for AT25128A-10PU-1.8 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 acquired Atmel in 2016 and maintains full product support, documentation, and manufacturing continuity for the AT25xxx family of serial EEPROMs.

The AT25128A-10PU-1.8 belongs to Microchip's SPI serial EEPROM product line, designed specifically for reliable, low-voltage, nonvolatile data storage in resource-constrained embedded systems where pin count, power budget, and long-term data integrity are critical.

FAQ

What is the maximum clock frequency supported by AT25128A-10PU-1.8?

The AT25128A-10PU-1.8 supports up to 20 MHz SCK frequency when VCC = 5.0 V, 10 MHz at 2.7 V–5.5 V, and 5 MHz at 1.8 V–5.5 V. These values are specified in Table 1-3 of the datasheet and reflect guaranteed AC timing performance across the industrial temperature range. The AT25128A-10PU-1.8 must be operated within these limits to ensure reliable read/write operations and proper setup/hold timing compliance.

Does AT25128A-10PU-1.8 support both SPI Mode 0 and Mode 3?

Yes, the AT25128A-10PU-1.8 explicitly supports SPI Modes 0 (CPOL = 0, CPHA = 0) and 3 (CPOL = 1, CPHA = 1), as stated in the Features section. Mode 0 operation is fully documented in the timing diagrams and AC characteristics; Mode 3 compatibility is confirmed by the device's bidirectional clock polarity handling and sample-on-falling-edge capability for SO output. The AT25128A-10PU-1.8 does not support Modes 1 or 2.

How does the HOLD pin function in AT25128A-10PU-1.8?

The HOLD pin on AT25128A-10PU-1.8 suspends ongoing SPI communication without resetting the internal command sequence. To pause, HOLD must be driven low while SCK is low; to resume, HOLD is returned high while SCK remains low. During HOLD, SI inputs are ignored and SO enters high-impedance state. This allows the host MCU to service interrupts or reallocate resources mid-transaction. The AT25128A-10PU-1.8 resumes exactly where it left off upon HOLD deassertion.

What package type is used for AT25128A-10PU-1.8?

The AT25128A-10PU-1.8 uses an 8-lead Plastic Dual In-line Package (PDIP) with 0.300" body width, per ordering code suffix "PU" and Package Type "8P3" in the datasheet's Ordering Information table. This through-hole package is distinct from SOIC, TSSOP, dBGA2, or SAP variants and is designated for industrial temperature range (−40°C to +85°C) with lead-free/halogen-free construction.

Can AT25128A-10PU-1.8 operate from a 1.8 V supply?

Yes, the AT25128A-10PU-1.8 is rated for 1.8 V to 5.5 V operation, as indicated by the "-1.8" suffix in its part number and confirmed in DC Characteristics Table 1-2 (VCC1 min = 1.8 V). At 1.8 V, it supports 5 MHz SCK max, retains full functionality including WRITE, READ, and status register access, and draws only 0.2 µA standby current. The AT25128A-10PU-1.8 maintains full timing and endurance specifications across this entire voltage range.