Microchip Technology 93LC56-I/SN

Overview

93LC56-I/SN from Microchip Technology Inc. is a 2 Kbit serial EEPROM with Microwire-compatible 3-wire interface, configurable as 256 × 8 or 128 × 16 organization via ORG pin, operating from 2.5 V to 5.5 V, and rated for industrial temperature range (−40°C to +85°C). It delivers 1 million erase/write cycles and 200-year data retention, used in microcontroller configuration storage and calibration data logging.

For engineers reviewing the 93LC56-I/SN datasheet, 93LC56-I/SN pinout, 93LC56-I/SN application, or 93LC56-I/SN equivalent, key selection criteria include its dual x8/x16 memory organization, self-timed erase/write with RDY/BSY status on DO, low 3 µA standby current at 2.5 V, and SOIC-8 package compatibility with JEDEC MS-012 standards.

Technical Context

The 93LC56-I/SN implements a synchronous serial Microwire interface with CS, CLK, DI, and DO pins, where instruction execution begins on a Start condition (CS high + DI high at CLK rising edge). Memory access is controlled by 9- or 10-bit address fields depending on ORG state, with opcode-driven command set including READ, WRITE, ERASE, ERAL, WRAL, EWEN, and EWDS.

It uses CMOS EEPROM technology with on-chip power-on/off protection that inhibits programming below 1.4 V, and requires explicit EWEN before any erase/write operation. The DO pin serves dual function: serial data output during READ and Ready/Busy status indicator during programming - low = busy, high = ready - provided CS is pulsed high after ≥250 ns low time (TCSL).

Key Specifications

Pinout & Package

93LC56-I/SN is housed in an 8-pin narrow SOIC package (JEDEC MS-012, 150 mil width), marked "I/SN" per Microchip's part numbering system. Pin 1 is CS, pin 2 is CLK, pin 3 is DI, pin 4 is DO, pin 5 is VSS, pin 6 is ORG, pin 7 is NU (not utilized), and pin 8 is VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC56-I/SN, the 93LC56C-I/SN offers identical functionality with improved robustness and roadmap support, while AT25020B-MAU-1.8 introduces interface and command-layer incompatibility requiring hardware and firmware adaptation.

Availability

93LC56-I/SN is available at Aetrix Electronics and suitable for microcontroller configuration storage, calibration data logging, power meter firmware patch storage, and POS terminal security key vault applications requiring stable component supply and industrial temperature compliance.

Supply support for 93LC56-I/SN 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 devices, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 93LC56-I/SN belongs to Microchip's legacy Microwire EEPROM product line, designed specifically for cost-sensitive, low-power embedded systems requiring simple serial nonvolatile storage with minimal pin count and firmware overhead.

FAQ

What memory organization options does the 93LC56-I/SN support?

The 93LC56-I/SN supports two memory configurations selected by the ORG pin: when ORG = VCC, it operates as 128 × 16 (2 Kbit x16); when ORG = VSS, it operates as 256 × 8 (2 Kbit x8). Floating ORG is permitted only at clock frequencies ≤1 MHz in x16 mode. This dual-mode capability is confirmed in DS21712C Tables 1-3 and 1-4 and Section 2.0.

Does the 93LC56-I/SN require external timing components for write operations?

No, the 93LC56-I/SN does not require external timing components. All erase and write cycles - including ERASE, WRITE, ERAL, and WRAL - are fully self-timed. Once initiated by the falling edge of CS, the device internally manages the 4 ms (per word), 8 ms (ERAL), or 16 ms (WRAL) durations. This is explicitly stated in Sections 2.6–2.9 and AC Characteristic Table entries TWC, TEC, and TWL of DS21712C.

How is Ready/Busy status monitored on the 93LC56-I/SN?

Ready/Busy status on the 93LC56-I/SN is monitored via the DO pin: DO = low indicates programming is in progress; DO = high indicates completion. To sample status, CS must be brought high for ≥250 ns after being low for ≥250 ns (TCSL), and the device must be in an active erase/write cycle. DO returns to high-Z when CS is low or during non-programming operations. This behavior is defined in Sections 2.6–2.9 and Figure 2-4 through 2-7 of DS21712C.

What is the minimum supply voltage for reliable operation of the 93LC56-I/SN?

The 93LC56-I/SN operates reliably down to 2.5 V for both read and programming functions, as specified in the Absolute Maximum Ratings and DC Characteristics tables of DS21712C. Programming is inhibited below 1.4 V by internal power-on reset circuitry, but functional operation (including read, EWEN, and status polling) is guaranteed from 2.5 V to 5.5 V. This is confirmed in Section 2.3 and Electrical Characteristics Table D1–D10.

Is the 93LC56-I/SN pin-compatible with the 93LC56X-I/SN variant?

No, the 93LC56-I/SN is not pin-compatible with the 93LC56X-I/SN. The "X" suffix denotes a rotated SOIC package (pin 1 = ORG, pin 3 = CS, etc.), whereas the standard 93LC56-I/SN follows JEDEC MS-012 pinout (pin 1 = CS, pin 6 = ORG). This distinction is clearly documented in the Package Marking Information section (DS21712C page 11) and Pin Function Table (page 10), where separate pin mappings are provided for SOIC and Rotated SOIC variants.