Microchip Technology AT93C56A-10TU-1.8

Overview

AT93C56A-10TU-1.8 from Microchip Technology (formerly Atmel) is a 2 Kbit serial EEPROM with user-selectable 256 × 8 or 128 × 16 organization, operating from 1.8 V to 5.5 V, featuring a three-wire interface (CS/SK/DI/DO), 2 MHz max clock rate at 5 V, and self-timed write cycles ≤10 ms. It is used in industrial control modules for parameter storage where low-voltage operation and space-constrained PCB layouts are critical.

For engineers reviewing the AT93C56A-10TU-1.8 datasheet, AT93C56A-10TU-1.8 pinout, AT93C56A-10TU-1.8 application, or AT93C56A-10TU-1.8 equivalent, key selection factors include voltage range compatibility (1.8–5.5 V), TSSOP-8 package footprint, ORG-pin configurable memory width, endurance of 1 million write cycles, and automotive-grade temperature support (−40°C to +85°C).

Technical Context

The AT93C56A-10TU-1.8 implements a synchronous three-wire serial interface with Chip Select (CS), Serial Clock (SK), and bidirectional data path (DI input / DO output). Its internal organization is dynamically selected via the ORG pin: tied to VCC enables 128 × 16 mode; grounded enables 256 × 8 mode.

Write operations require prior execution of the EWEN instruction to enter Erase/Write Enable state; all programming instructions (ERASE, WRITE, ERAL, WRAL) are disabled until then. The DO pin provides Ready/Busy status during active write/erase cycles when CS is asserted after tCS ≥250 ns, enabling host synchronization without polling overhead.

Key Specifications

Pinout & Package

AT93C56A-10TU-1.8 is packaged in an 8-lead Thin Shrink Small Outline Package (TSSOP), 0.170" wide body, RoHS-compliant, lead-free, with 0.65 mm pitch and exposed pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M95256-DRMN6TP/K and AT25020B-MAHL-T, the AT93C56A-10TU-1.8 offers unique ORG-pin configurability and minimal pin count (8-pin TSSOP), making it optimal for space-constrained, low-pin-count MCU designs requiring exactly 2 Kbit with flexible word width - whereas alternatives trade pin efficiency for speed or density.

Availability

AT93C56A-10TU-1.8 is available at Aetrix Electronics and suitable for industrial sensor calibration, motor drive parameter storage, and smart meter firmware settings requiring stable component supply across extended production lifecycles.

Supply support for AT93C56A-10TU-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 is a global semiconductor company specializing in microcontrollers, analog devices, and nonvolatile memory solutions, with broad industrial and automotive qualification coverage.

The AT93C56A-10TU-1.8 belongs to Microchip's legacy serial EEPROM product line, designed specifically for cost-sensitive, space-constrained embedded systems needing reliable, low-voltage, pin-efficient nonvolatile storage.

FAQ

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

The ORG pin on the AT93C56A-10TU-1.8 selects internal memory organization: connecting to VCC configures 128 × 16 mode, grounding configures 256 × 8 mode, and leaving unconnected defaults to 128 × 16 via internal ~1 MΩ pull-up. This hardware-selectable width eliminates firmware address translation and simplifies integration with 8-bit or 16-bit data paths. The AT93C56A-10TU-1.8 requires no external pull-up/down resistors unless noise immunity is critical in high-EMI environments.

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

Yes, the AT93C56A-10TU-1.8 supports sequential read: after initiating a READ instruction, holding CS high causes automatic increment of the internal address pointer and continuous clocking of subsequent memory locations on DO without reissuing the instruction. A dummy bit ('0') precedes the first data byte but is omitted between successive words, enabling efficient bulk reads. This behavior is fully supported in both 256 × 8 and 128 × 16 modes of the AT93C56A-10TU-1.8.

What is the minimum CS low time required for valid instruction execution on the AT93C56A-10TU-1.8?

The AT93C56A-10TU-1.8 requires a minimum CS low time (tCS) of 250 ns for reliable instruction decoding across its full 1.8–5.5 V supply range. This timing applies to all instructions including READ, EWEN, ERASE, WRITE, ERAL, WRAL, and EWDS. Violating tCS may result in missed commands or undefined behavior. The AT93C56A-10TU-1.8 datasheet specifies this as an absolute minimum - robust designs should use ≥500 ns to accommodate signal rise/fall times and board-level jitter.

How does the AT93C56A-10TU-1.8 indicate Ready/Busy status during write cycles?

The AT93C56A-10TU-1.8 outputs Ready/Busy status on the DO pin when CS is brought high after being held low for ≥250 ns (tCS) during an active write or erase cycle. A logic '1' indicates completion and readiness for next instruction; a logic '0' indicates ongoing operation. This status is only valid while CS remains high and is not available after the self-timed write cycle (tWP ≤10 ms) completes. Host firmware must monitor DO during this window to avoid premature command issuance on the AT93C56A-10TU-1.8.

Is the AT93C56A-10TU-1.8 pin-compatible with the AT93C56A-10TU-2.7 variant?

Yes, the AT93C56A-10TU-1.8 and AT93C56A-10TU-2.7 share identical TSSOP-8 pinout, mechanical dimensions, and functional pin assignments (CS, SK, DI, DO, VCC, GND, ORG, NC). The sole difference is the guaranteed minimum supply voltage: −1.8 supports 1.8–5.5 V operation, while −2.7 requires ≥2.7 V. Both variants use the same die and packaging, allowing direct substitution in existing layouts if voltage compliance is verified. No PCB changes are needed when replacing AT93C56A-10TU-2.7 with AT93C56A-10TU-1.8 in 1.8 V systems.