Microchip Technology 93C76C-E/ST

Overview

93C76C-E/ST from Microchip Technology Inc. is an 8Kbit, 4.5–5.5V serial EEPROM with programmable 8-/16-bit word organization via ORG pin and full-array write protection via PE pin. It supports Microwire-compatible 3-wire interface (CS/CLK/DI/DO), delivers 1M erase/write cycles and >200-year data retention, and is used in automotive infotainment control storage for configuration persistence across power cycles.

For engineers reviewing the 93C76C-E/ST datasheet, 93C76C-E/ST pinout, 93C76C-E/ST application, or 93C76C-E/ST equivalent, key selection criteria include VCC range (4.5–5.5V), industrial/automotive temperature grade (–40°C to +125°C), ORG/PE pin dependency for memory configuration and write enable, and self-timed 2ms write cycle timing.

Technical Context

The 93C76C-E/ST implements a synchronous Microwire-compatible serial interface with CS-active-high selection, rising-edge clocked DI input, and DO output supporting both data readout and Ready/Busy status polling. Its dual-word-size architecture requires external logic level on ORG to select x8 (ORG = VSS) or x16 (ORG = VCC) mode, while PE must be held high to permit erase/write operations.

Internal power-on reset and voltage detect circuitry (VPOR = 3.8V) inhibit all programming below VCC threshold; EWEN/EWDS commands provide software-level write protection. All erase/write cycles-including ERAL (6ms) and WRAL (15ms)-are fully self-timed and require no external clocking after initiation.

Key Specifications

Pinout & Package

93C76C-E/ST is packaged in 8-lead TSSOP (ST), with Pb-free Matte Tin finish and pin 1 marked by laser. The package supports surface-mount reflow and fits standard 0.65 mm pitch footprints.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC76C-E/ST, the 93C76C-E/ST provides higher VCC immunity for direct 5V battery rail interfacing and stronger brownout protection (3.8V vs 1.5V VPOR), while AT25DF041A-SSH-T offers SPI speed and density at the cost of interface redesign and voltage limitation.

Availability

93C76C-E/ST is available at Aetrix Electronics and suitable for automotive infotainment, body control modules, and engine management systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 93C76C-E/ST 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 93Cxx series was designed specifically for automotive and industrial applications demanding high reliability, extended temperature operation, and hardware-enforced data integrity - exemplified by dedicated PE and ORG pins in the 93C76C-E/ST variant.

FAQ

What is the function of the ORG pin on the 93C76C-E/ST?

The ORG pin on the 93C76C-E/ST selects memory organization: tied to VCC for 512 × 16-bit mode, or to VSS for 1024 × 8-bit mode. This pin is absent on 93C76A/B variants and must be hardwired - not floated - to ensure deterministic behavior. The 93C76C-E/ST uses this pin to adapt its data interface width to match host MCU requirements without external multiplexing logic.

How does the Program Enable (PE) pin protect memory on the 93C76C-E/ST?

The PE pin on the 93C76C-E/ST acts as a hardware write gate: only when PE is high can EWEN, ERASE, or WRITE commands execute. If PE is low, all programming functions are disabled regardless of software state - a critical feature for preventing accidental corruption during CAN bus activity or power transients. This hardware lock complements the EWEN/EWDS software commands in the 93C76C-E/ST instruction set.

What is the minimum VCC required for reliable operation of the 93C76C-E/ST?

The 93C76C-E/ST requires VCC ≥ 4.5 V for full specification compliance, with a voltage detect threshold (VPOR) of 3.8 V. Below 4.5 V, AC timing parameters (e.g., FCLK max = 3 MHz) and write endurance are not guaranteed. Operation below 3.8 V disables all programming modes - a built-in safeguard that prevents partial writes during brownout conditions in automotive 93C76C-E/ST deployments.

Can the 93C76C-E/ST be used in place of the 93C76A-E/ST or 93C76B-E/ST?

No - the 93C76C-E/ST is not a drop-in replacement for 93C76A-E/ST or 93C76B-E/ST due to pinout differences: it adds ORG and PE pins not present on A/B variants. While electrically compatible in x8 or x16 mode, PCB layout must accommodate the extra pins and correct pull-up/down biasing. The 93C76C-E/ST also requires explicit PE assertion for writes, unlike A/B versions where programming is always enabled.

What is the maximum clock frequency supported by the 93C76C-E/ST at 5.0 V VCC?

At VCC = 5.0 V (within the 4.5–5.5 V range), the 93C76C-E/ST supports a maximum clock frequency (FCLK) of 3 MHz, per Table 1-2. This applies to all instructions including READ, WRITE, and EWEN. Timing margins (e.g., TCKH ≥ 200 ns, TCKL ≥ 100 ns) must be maintained; exceeding 3 MHz risks setup/hold violations and command misinterpretation in the 93C76C-E/ST serial interface.