Microchip Technology 93C56C-I/P

Overview

93C56C-I/P from Microchip Technology Inc. is a 2 Kbit serial EEPROM with Microwire-compatible 3-wire interface, ORG pin for dynamic 8-/16-bit word size selection, and industrial temperature range (–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 where voltage tolerance and nonvolatile retention are critical.

For engineers reviewing the 93C56C-I/P datasheet, 93C56C-I/P pinout, 93C56C-I/P application, or 93C56C-I/P equivalent, key selection considerations include VCC range (4.5–5.5 V), ORG-configurable organization, Ready/Busy status via DO pin, and compatibility with legacy Microwire controllers in space-constrained industrial PCBs.

Technical Context

The 93C56C-I/P implements a synchronous serial interface with CS, CLK, and DI/DO pins operating at up to 3 MHz (VCC ≥ 4.5 V). Its ORG pin directly selects between 256 × 8-bit (ORG = low) and 128 × 16-bit (ORG = high) memory mapping - no internal decoding logic required.

Write operations use auto-erase-before-write architecture initiated by rising CLK edge on final data bit (93C-series behavior), with DO pin providing real-time Ready/Busy polling. Power-on reset circuitry disables writes below 3.8 V, and EWEN/EWDS commands enforce explicit write-enable discipline.

Key Specifications

Pinout & Package

8-lead PDIP package (P suffix), through-hole mounting, 0.3-inch body width. Pin 1 marked with notch or dot; pin 1 is CS.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC56C-I/P and 93AA56C-I/P, the 93C56C-I/P offers highest noise immunity and VCC stability in pure 5 V industrial environments but lacks flexibility for lower-voltage domains - making it optimal for legacy 5 V control systems where voltage headroom and ESD robustness (>4 kV) are prioritized.

Availability

93C56C-I/P is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and medical device manufacturing requiring stable component supply, long-term lifecycle support, and RoHS-compliant through-hole packaging.

Supply support for 93C56C-I/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 microcontroller, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 93Cxx EEPROM family was designed specifically for cost-sensitive, space-constrained industrial and automotive applications requiring reliable nonvolatile storage with minimal external components and proven Microwire compatibility.

FAQ

What is the function of the ORG pin on the 93C56C-I/P?

The ORG pin on the 93C56C-I/P selects memory organization: logic high (≥0.7 VCC) configures 128 × 16-bit mode, logic low (≤0.2 VCC) configures 256 × 8-bit mode. It is an active input - not NC - and must be externally biased to a valid logic level for reliable operation. This capability is exclusive to 'C' variants like the 93C56C-I/P.

Does the 93C56C-I/P require external pull-up resistors on its I/O lines?

The 93C56C-I/P does not require external pull-ups on CS, CLK, or DI for basic operation, but a 10 kΩ pull-down on CS is recommended per Microchip application guidance to prevent spurious activation during power-up. DO is actively driven during read/status and tri-states otherwise, so pull-ups are unnecessary unless shared with DI in single-wire configurations - in which case a series resistor is mandatory.

How does the 93C56C-I/P handle power loss during a write cycle?

The 93C56C-I/P incorporates hardware power-loss protection: its internal POR circuit disables all write operations when VCC drops below 3.8 V, preventing partial writes or data corruption. Combined with auto-erase-before-write and 1,000,000 endurance, this ensures that even interrupted erase/write cycles leave memory in a known, recoverable state - no software recovery routines needed.

Can the 93C56C-I/P be used with modern SPI controllers?

The 93C56C-I/P implements Microwire protocol - a subset of SPI with single bidirectional data line (DI/DO), fixed MSB-first transmission, and no mode or clock polarity configuration. While many SPI peripherals can emulate Microwire timing, true SPI mode (CPOL/CPHA) is not supported. Direct interface requires either a dedicated Microwire master or bit-banged GPIO implementation matching the 93C56C-I/P's strict timing (e.g., TCKH ≥ 200 ns at 5 V).

What is the maximum clock frequency supported by the 93C56C-I/P at 5.0 V?

At VCC = 5.0 V (within the 4.5–5.5 V range), the 93C56C-I/P supports a maximum clock frequency of 3 MHz, as specified in Table 1-2 (A1 parameter). This allows full-speed operation in 5 V microcontroller systems without clock division, enabling rapid configuration reads or bulk writes using WRAL.