Microchip Technology 93LC56CT-I/MNY

Overview

93LC56CT-I/MNY from Microchip Technology Inc. is a 2 Kbit (256 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 2.5–5.5 V supply range, and Industrial temperature grade (–40°C to +85°C). It features self-timed erase/write cycles, automatic ERAL before WRAL, and Ready/Busy status via DO pin. Used for configuration storage in microcontroller-based embedded systems requiring nonvolatile parameter retention.

For engineers reviewing the 93LC56CT-I/MNY datasheet, 93LC56CT-I/MNY pinout, 93LC56CT-I/MNY application, or 93LC56CT-I/MNY equivalent, key selection criteria include its 8-bit organization (no ORG pin), TSSOP-8 package, 1 million erase/write endurance, 200-year data retention, and compatibility with legacy Microwire controllers in space-constrained industrial control modules.

Technical Context

This device implements a synchronous serial interface with CS, CLK, and DI/DO pins operating at up to 3 MHz (VCC ≥ 4.5 V). It uses a dedicated 8-bit memory map (256 × 8) with no ORG pin - confirming fixed x8 organization per Device Selection Table. All instructions (READ, WRITE, ERASE, ERAL, WRAL, EWEN/EWDS) are executed via rising-edge clocked bit streams starting with a Start condition (CS high + DI high on CLK edge).

Power-on data protection is enforced by internal voltage detection (VPOR = 1.5 V typical); write operations require prior EWEN command and are inhibited below VPOR. The DO pin serves dual function: serial data output during READ and Ready/Busy status indicator during programming - asserted low until completion of self-timed TWC = 6 ms erase/write cycle.

Key Specifications

Pinout & Package

93LC56CT-I/MNY is housed in an 8-lead TSSOP (Thin Shrink Small Outline Package) with 0.65 mm pitch, JEDEC MO-153 compliant, and Pb-free Matte Tin finish. Pin 1 is marked by laser dot; exposed pad not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC56B-I/MNY, the 93LC56CT-I/MNY provides native 8-bit compatibility and identical pinout but excludes 16-bit flexibility; versus AT25020B-MAHL-T, it retains Microwire legacy support and hardware-ready signaling at the cost of SPI interoperability.

Availability

93LC56CT-I/MNY is available at Aetrix Electronics and suitable for industrial control systems, smart sensor modules, and energy metering equipment requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for 93LC56CT-I/MNY 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 93LC56 series belongs to Microchip's legacy Microwire-compatible serial EEPROM product line, designed specifically for cost-sensitive, space-constrained embedded systems needing reliable nonvolatile storage with minimal pin count and software overhead.

FAQ

What is the memory organization of the 93LC56CT-I/MNY?

The 93LC56CT-I/MNY is a fixed 256 × 8-bit (2 Kbit) device with no ORG pin - confirming x8-only organization. Unlike 'C' variants, 'A' versions like this part do not support runtime word-size switching. This simplifies interface design in 8-bit microcontroller systems where byte-aligned access is standard and eliminates need for external ORG pull-up/down logic.

Does the 93LC56CT-I/MNY require an external pull-up resistor on the DO pin?

No, the 93LC56CT-I/MNY does not require an external pull-up on DO. The DO pin actively drives high/low during READ and Ready/Busy status reporting, and enters High-Z when inactive. However, if DI and DO are shorted on a shared bus, a current-limiting resistor (e.g., 10 kΩ) is required between them to prevent bus conflict during the dummy zero phase of READ, as specified in Section 2.2 of DS21794G.

What is the maximum clock frequency supported by the 93LC56CT-I/MNY?

The 93LC56CT-I/MNY supports up to 3 MHz clock frequency when VCC is 4.5 V to 5.5 V. At 2.5 V ≤ VCC < 4.5 V, maximum clock frequency is 2 MHz. These limits are defined in Table 1-2 (AC Characteristics) of DS21794G and reflect timing margins for reliable setup/hold and propagation across the Industrial temperature range.

How is write protection implemented in the 93LC56CT-I/MNY?

Write protection in the 93LC56CT-I/MNY is implemented via EWEN (Erase/Write Enable) and EWDS (Erase/Write Disable) commands. The device powers up in EWDS mode, blocking all erase/write operations until EWEN is issued. After any write, executing EWDS re-locks the memory. This two-command scheme prevents accidental writes during power transients or software faults, and is independent of READ functionality.

Is the 93LC56CT-I/MNY pin-compatible with other 93LC56x variants in TSSOP-8?

Yes, the 93LC56CT-I/MNY is pin-compatible with all 93LC56x variants (A/B/C) in TSSOP-8 (ST package code), including 93LC56A-I/MNY, 93LC56B-I/MNY, and 93LC56C-I/MNY. Pin functions match per Table 3-1: CS (1), CLK (2), DI (3), DO (4), VSS (5), NC (6), ORG (7), VCC (8). Note that ORG is NC on 'A'/'B' parts and functional only on 'C' variants - no PCB change is needed when substituting within same package.