Microchip Technology 93LC76C-E/P

Overview

The 93LC76C-E/P from Microchip Technology Inc. is an 8 Kbit, low-voltage, serial Electrically Erasable PROM (EEPROM) with selectable 8-bit or 16-bit word organization via the ORG pin, program enable (PE) write protection, and industrial/automotive temperature support (–40°C to +125°C). It operates from 2.5V to 5.5V, supports Microwire-compatible 3-wire serial interface (CS/CLK/DI/DO), and delivers 1 million erase/write cycles with >200 years data retention - used in automotive body control modules for calibration storage.

For engineers reviewing the 93LC76C-E/P datasheet, 93LC76C-E/P pinout, 93LC76C-E/P application, or 93LC76C-E/P equivalent, key selection considerations include VCC range compatibility (2.5–5.5 V), ORG/PE pin configuration for memory width and write lock, Ready/Busy status polling via DO, self-timed erase/write timing (5 ms typical), and Pb-free PDIP package suitability for through-hole rework and high-reliability automotive PCBs.

Technical Context

This device implements a synchronous Microwire-compatible serial interface with start-bit detection, opcode-driven command set (READ, WRITE, ERASE, WRAL, EWEN/EWDS), and hardware-controlled memory organization selection. The ORG pin determines whether the 1024×8-bit or 512×16-bit array is active, while the PE pin must be driven high to enable programming - both pins are dedicated to the 'C' variant and absent on 'A'/'B' versions.

Internal logic includes automatic ERAL before WRAL, power-on/off data protection, and status reporting via DO pin (low = busy, high = ready) during erase/write operations. All programming requires prior EWEN execution, and the device powers up in EWDS mode to prevent accidental writes - critical for safety-critical automotive firmware parameter storage.

Key Specifications

Pinout & Package

Package: 8-lead PDIP (Plastic Dual In-line Package), Pb-free Matte Tin finish, through-hole mount, 0.3 inch body width.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC76C-I/P, the 93LC76C-E/P adds automotive temperature qualification and tighter VCC min specification (2.5 V vs. same), while AT25DF041A-SSH-T trades hardware-configurable organization and write lock for higher density and SPI compatibility - neither offers drop-in replacement capability.

Availability

The 93LC76C-E/P is available at Aetrix Electronics and suitable for automotive electronics, industrial motor control, and medical device design requiring stable component supply, long-lifecycle support, and AEC-Q100-aligned nonvolatile memory.

Supply support for 93LC76C-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, with global manufacturing and support infrastructure.

The 93LC76C-E/P belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, low-pin-count embedded systems requiring robust, hardware-protected nonvolatile storage in harsh environments.

FAQ

What is the function of the ORG pin on the 93LC76C-E/P?

The ORG pin on the 93LC76C-E/P selects memory organization: tied to VCC it configures the device as 512 × 16-bit; tied to VSS it configures as 1024 × 8-bit. This pin is exclusive to 'C' variants and must be hardwired - floating is not permitted. The 93LC76C-E/P uses this pin to maintain backward compatibility with both 8-bit and 16-bit microcontroller data buses without requiring separate SKUs.

How does the PE pin protect memory on the 93LC76C-E/P?

The PE (Program Enable) pin on the 93LC76C-E/P must be driven high to permit any erase or write operation; when held low, the entire memory array is hardware write-protected regardless of software commands. This prevents corruption during power transients or firmware faults. Unlike software locks, the 93LC76C-E/P PE pin provides unconditional, instantaneous protection independent of MCU state.

What is the maximum clock frequency supported by the 93LC76C-E/P at 3.3 V?

At VCC = 3.3 V (within 2.5–4.5 V range), the 93LC76C-E/P supports a maximum clock frequency of 2 MHz per Table 1-2 (A1). This limit ensures reliable setup/hold timing for DI and CS signals and accounts for propagation delays across the specified voltage and temperature range. Exceeding 2 MHz may cause command misreads or incomplete writes.

Does the 93LC76C-E/P require an external pull-up resistor on the DO pin?

No, the 93LC76C-E/P does not require an external pull-up on DO. The output buffer actively drives high or low during read/status mode and enters High-Z when CS is low or during non-read states. However, if DI and DO are shorted for single-wire operation, a current-limiting resistor (e.g., 10 kΩ) is required between them to prevent bus conflict when A0 = high during dummy-zero phase.

What is the purpose of the EWEN and EWDS instructions in the 93LC76C-E/P command set?

The EWEN (Erase/Write Enable) and EWDS (Erase/Write Disable) instructions control programming permission: 93LC76C-E/P powers up in EWDS mode, blocking all erase/write until EWEN is issued. After programming, issuing EWDS relocks the array. These commands add software-level protection that complements the hardware PE pin - enabling secure multi-step update sequences in automotive firmware.