Microchip Technology 93C76A-I/ST

Overview

93C76A-I/ST from Microchip Technology Inc. is an 8K-bit, 1024 × 8-bit organization serial EEPROM with Microwire-compatible 3-wire interface (CS, CLK, DI/DO), operating at 4.5–5.5V supply, rated for -40°C to +85°C industrial temperature range, and housed in an 8-lead TSSOP package. It delivers nonvolatile data storage for embedded control systems requiring robust write endurance and power-loss protection.

For engineers reviewing the 93C76A-I/ST datasheet, 93C76A-I/ST pinout, 93C76A-I/ST application, or 93C76A-I/ST equivalent, key selection criteria include its fixed 8-bit word size, absence of ORG and PE pins, 2 ms erase/write cycle time at VCC ≥4.5V, Ready/Busy status via DO pin, and compatibility with legacy Microwire host controllers in space-constrained industrial designs.

Technical Context

The 93C76A-I/ST implements a synchronous serial Microwire interface with start-bit detection, opcode-driven command set (READ, WRITE, ERASE, ERAL, WRAL, EWEN/EWDS), and self-timed internal auto-erase before write. It uses a dedicated 8-bit memory array with no external configuration pins-unlike C-versions-ensuring deterministic timing and eliminating ORG/PE logic dependencies.

Its operation relies on CS-active-high selection, rising-edge clocked data transfer, and DO pin dual-role functionality: serial data output during READ and active-low Ready/Busy signaling during programming cycles. Power-on reset circuitry enforces VCC ≥3.8V for reliable operation, and all instructions require precise clock cycle counts per instruction set (e.g., 22 CLK cycles for READ).

Key Specifications

Pinout & Package

8-lead TSSOP (ST) package: compact 4.4 mm × 3.0 mm footprint, exposed pad optional, RoHS-compliant matte tin finish. Pin 1 marked by laser dot; pin 1 ID corner defined per JEDEC MO-153.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC76A-I/ST and AT25080B-SSHL-T, the 93C76A-I/ST delivers the fastest write performance (2 ms) within its 4.5–5.5V window and preserves legacy Microwire timing behavior-critical for drop-in replacements in mature industrial platforms where VCC stability is guaranteed.

Availability

93C76A-I/ST is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and medical device configuration storage requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for 93C76A-I/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 components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 93C76A-I/ST belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, space-constrained industrial and automotive applications demanding proven reliability, low-pin-count interfaces, and long-term data integrity without complex configuration.

FAQ

What is the maximum clock frequency supported by the 93C76A-I/ST?

The 93C76A-I/ST supports up to 3 MHz clock frequency when VCC is 4.5–5.5V. This timing is validated across the full industrial temperature range (-40°C to +85°C) and enables efficient data transfer without violating setup/hold requirements. The device does not require continuous clocking during write cycles, allowing host processors to manage bus bandwidth dynamically while maintaining full 93C76A-I/ST functionality.

Does the 93C76A-I/ST have an ORG pin or Program Enable (PE) pin?

No, the 93C76A-I/ST does not include ORG or PE pins. As an 'A'-version device, it features fixed 8-bit organization and always-enabled write capability-unlike 'C'-versions which require external logic for word-size selection and write protection. This simplifies PCB routing and eliminates external pull-up/down resistors, making the 93C76A-I/ST ideal for designs where memory configuration is static and firmware-controlled write enable suffices.

How is Ready/Busy status monitored on the 93C76A-I/ST?

Ready/Busy status on the 93C76A-I/ST is monitored via the DO pin: it drives low during active erase or write operations and returns high upon completion. To sample status, CS must be brought high after ≥250 ns low time (TCSL); DO then reflects device readiness synchronously with CLK. This hardware-based polling eliminates software timeouts and ensures deterministic timing-critical for real-time systems relying on the 93C76A-I/ST for mission-critical parameter storage.

What is the write endurance and data retention specification for the 93C76A-I/ST?

The 93C76A-I/ST guarantees 1,000,000 erase/write cycles and minimum 200 years of data retention at 25°C. These specifications are characterized across the full industrial temperature range and apply to all bits in the 1024 × 8-bit array. Endurance testing follows JEDEC standards under worst-case VCC (5.0V) and temperature conditions, ensuring the 93C76A-I/ST meets long-service-life requirements in applications such as industrial controllers and utility meters.

Which packages are available for the 93C76A-I/ST, and what does '-I/ST' signify?

The '-I/ST' suffix in 93C76A-I/ST indicates Industrial temperature grade (-40°C to +85°C) and 8-lead TSSOP package (ST). Other available packages for the 93C76A include PDIP (P), SOIC (SN), MSOP (MS), and DFN/TDFN (MC/MN), but the -I/ST variant is specifically qualified and marked for TSSOP. The TSSOP footprint (4.4 mm × 3.0 mm) supports high-density layouts while maintaining hand-solderability and automated assembly compatibility-key for cost-sensitive 93C76A-I/ST deployments.