Microchip Technology 93C56C-E/P

Overview

93C56C-E/P from Microchip Technology Inc. is a 2 Kbit low-voltage serial EEPROM with Microwire-compatible 3-wire interface, ORG-pin-selectable 8-/16-bit word organization, and industrial-temperature operation (–40°C to +85°C). It features self-timed erase/write cycles, automatic ERAL before WRAL, power-on/off data protection, and 1,000,000 endurance cycles - used in embedded system configuration storage and calibration data retention.

For engineers reviewing the 93C56C-E/P datasheet, 93C56C-E/P pinout, 93C56C-E/P application, or 93C56C-E/P equivalent, key selection considerations include VCC range (4.5–5.5 V), ORG-driven word-size flexibility, Ready/Busy status via DO, sequential read capability, and Pb-free 8-lead PDIP packaging for through-hole legacy designs.

Technical Context

The 93C56C-E/P implements a synchronous serial Microwire interface with CS, CLK, and DI/DO signals. Its ORG pin directly configures memory mapping between 256 × 8-bit (ORG = 0) and 128 × 16-bit (ORG = 1), enabling hardware-selectable data bus width without firmware changes.

Internal logic enforces EWEN/EWDS protocol for write protection: device powers up in EWDS state, requiring explicit EWEN before any erase or write. All programming operations (ERASE, WRITE, ERAL, WRAL) are self-timed and generate Ready/Busy status on DO when CS is reasserted after TCSL ≥ 250 ns.

Key Specifications

Pinout & Package

8-lead PDIP (P package) with 0.3-inch body width; lead finish is Pb-free Matte Tin. 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 NC, pin 8 is VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC56C-E/P and 93AA56C-E/P, the 93C56C-E/P provides highest noise margin and ESD robustness at 5 V but lacks low-voltage flexibility - making it optimal for fixed 5 V industrial control boards where supply stability is assured.

Availability

93C56C-E/P is available at Aetrix Electronics and suitable for industrial motor drives, sensor calibration modules, PLC I/O expansion, and medical device audit logging requiring stable component supply and long-term obsolescence management.

Supply support for 93C56C-E/P 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.

The 93Cxx family was designed specifically for cost-sensitive, space-constrained industrial and automotive applications requiring reliable nonvolatile storage with minimal pin count and robust power-supply immunity.

FAQ

What is the minimum VCC voltage required for reliable operation of the 93C56C-E/P?

The 93C56C-E/P requires a minimum VCC of 4.5 V for all operations. Its internal voltage detector disables erase/write functions below 3.8 V to prevent data corruption. Unlike the 93LC56C-E/P or 93AA56C-E/P variants, it does not support operation at 2.5 V or 1.8 V - using it below 4.5 V will result in inhibited programming and undefined read behavior. Always verify supply stability within this window in 5 V systems.

How does the ORG pin affect memory access in the 93C56C-E/P?

The ORG pin on the 93C56C-E/P selects between two fixed memory organizations: logic high (VCC) configures 128 × 16-bit mode, while logic low (VSS) configures 256 × 8-bit mode. This setting determines instruction length, address width (7 vs. 8 bits), and data output width (16 vs. 8 bits). The 93C56C-E/P does not auto-detect bus width - ORG must be statically tied before power-up and remain stable during operation.

Can the 93C56C-E/P be used in place of a 93C56A-E/P or 93C56B-E/P?

No - the 93C56C-E/P is not a drop-in replacement for 93C56A-E/P or 93C56B-E/P. While pin-compatible, the 'A' and 'B' versions lack the ORG pin (replaced by NC), locking them to fixed 8-bit or 16-bit organization respectively. Substituting 93C56C-E/P requires hardware modification to route ORG and firmware updates to handle dynamic word-size selection - the 93C56C-E/P's ORG functionality introduces behavioral differences absent in A/B variants.

What is the purpose of the NC pin (Pin 7) on the 93C56C-E/P PDIP package?

Pin 7 on the 93C56C-E/P is designated NC (No Connection) and has no internal connection to die circuitry. It may be left unconnected on the PCB or used as a mechanical anchor point. Unlike the ORG pin (Pin 6), it serves no functional role in memory configuration or timing. This differs from A/B variants where Pin 6 is NC and Pin 7 is unused - the 93C56C-E/P repurposes Pin 6 for ORG, making Pin 7 the sole NC terminal in its 8-pin PDIP layout.

Does the 93C56C-E/P support sequential read, and how is it enabled?

Yes, the 93C56C-E/P supports sequential read: after issuing a READ instruction and outputting the first byte/word, subsequent data words automatically increment the internal address counter and appear on DO as long as CS remains high and CLK continues. No additional opcode is needed - the feature is inherent to the READ command execution. This reduces host MCU overhead and enables efficient bulk reads of configuration blocks without repeated instruction framing.