Microchip Technology AT93C56A-10PU-1.8

Overview

AT93C56A-10PU-1.8 from Microchip Technology (formerly Atmel) is a 2K-bit, three-wire serial EEPROM with user-selectable 256 × 8 or 128 × 16 organization, operating from 1.8 V to 5.5 V, featuring self-timed write cycles (≤10 ms), 1 million write endurance, and 100-year data retention. It is used in industrial control modules for parameter storage under low-voltage battery-backed operation.

For engineers reviewing the AT93C56A-10PU-1.8 datasheet, AT93C56A-10PU-1.8 pinout, AT93C56A-10PU-1.8 application, or AT93C56A-10PU-1.8 equivalent, key selection considerations include its 1.8 V minimum supply, ORG-pin configurable memory width, 2 MHz max clock at 5 V, 8-lead PDIP package, and compatibility with legacy Atmel serial EEPROM designs requiring RoHS-compliant industrial-temperature operation.

Technical Context

The AT93C56A-10PU-1.8 implements a synchronous three-wire interface (CS, SK, DI/DO) with instruction-based command set including READ, WRITE, ERASE, EWEN, and EWDS. Its internal logic decodes 9-bit addresses for x8 mode or 8-bit addresses for x16 mode based on ORG pin state, supporting sequential read without dummy bits after the first location.

Write operations require explicit Erase/Write Enable (EWEN) before programming; the device enters Erase/Write Disable (EWDS) state on power-up for data integrity. Ready/Busy status is reported via DO during CS high after tCS ≥ 250 ns, enabling host polling without fixed delay timing.

Key Specifications

Pinout & Package

AT93C56A-10PU-1.8 uses an 8-lead Plastic Dual Inline Package (PDIP), JEDEC MS-001 BA compliant, with 0.300" body width, 0.100" lead pitch, and through-hole mounting. Pin 1 is marked by notch or dot; pin numbering follows standard DIP convention (counterclockwise from notch).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT93C56B-10PU-1.8, the AT93C56A-10PU-1.8 offers proven field reliability with known timing margins but lacks updated ESD hardening; versus M95256-WMN6TP, it retains minimal GPIO usage and legacy compatibility at the cost of bandwidth and density.

Availability

AT93C56A-10PU-1.8 is available at Aetrix Electronics and suitable for industrial control systems, energy metering platforms, and medical device configuration storage requiring stable component supply and long-lifecycle support.

Supply support for AT93C56A-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 legacy serial EEPROM product lines with full documentation, qualification, and long-term supply commitment.

The AT93C56A series belongs to Microchip's legacy serial EEPROM portfolio, designed for cost-sensitive, low-pin-count embedded systems needing reliable nonvolatile storage in space-constrained industrial and commercial applications.

FAQ

What is the function of the ORG pin on the AT93C56A-10PU-1.8?

The ORG pin on the AT93C56A-10PU-1.8 selects internal memory organization: tied to VCC for 128 × 16 (x16) mode, grounded for 256 × 8 (x8) mode. When left unconnected, the internal 1 MΩ pull-up defaults to x16 mode. This hardware-selectable configuration allows the same AT93C56A-10PU-1.8 part to serve both byte- and word-oriented firmware architectures without changing the BOM.

Does the AT93C56A-10PU-1.8 support sequential read operations?

Yes, the AT93C56A-10PU-1.8 supports sequential read: after the initial READ instruction, holding CS low causes automatic address increment and continuous data output on DO without reissuing the instruction. The dummy bit (logic "0") appears only before the first data byte/word; subsequent words stream contiguously, enabling efficient bulk reads of calibration tables or configuration blocks.

What is the maximum clock frequency supported by the AT93C56A-10PU-1.8 at 1.8 V?

The AT93C56A-10PU-1.8 supports a maximum SK clock frequency of 0.25 MHz when operated at VCC = 1.8 V, as specified in Table 3-3 AC Characteristics. This limit ensures reliable setup/hold timing for DI and proper DO propagation under low-voltage conditions; at 5.0 V, the max clock increases to 2 MHz.

How does the AT93C56A-10PU-1.8 indicate write completion during polling?

The AT93C56A-10PU-1.8 indicates write completion via the DO pin: after initiating a WRITE, ERASE, or WRAL instruction, the host can bring CS high (after tCS ≥ 250 ns) and sample DO - a logic "1" means the operation completed successfully and the device is ready; a logic "0" means programming is still in progress. This Ready/Busy polling eliminates fixed-delay waits in firmware.

Is the AT93C56A-10PU-1.8 RoHS compliant and lead-free?

Yes, the AT93C56A-10PU-1.8 is RoHS compliant and lead-free, as indicated by the "U" suffix in the ordering code per Atmel's packaging notes. It meets EU Directive 2011/65/EU and is halogen-free, making it suitable for environmentally regulated industrial and medical electronics production.