Microchip Technology 93LC46A-I/PG

Overview

93LC46A-I/PG from Microchip Technology Inc. is a 1Kbit (128 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 2.5–5.5 V supply range, industrial temperature grade (–40°C to +85°C), and PDIP-8 package. It features self-timed erase/write cycles, automatic ERAL before WRAL, and Ready/Busy status via DO pin - used for configuration storage in microcontroller-based embedded systems.

For engineers reviewing the 93LC46A-I/PG datasheet, 93LC46A-I/PG pinout, 93LC46A-I/PG application, or 93LC46A-I/PG equivalent, key selection criteria include its fixed 8-bit organization (no ORG pin), 1 million erase/write endurance, >200-year data retention, and compatibility with legacy Microwire controllers requiring CS/CLK/DI/DO timing compliance per DS20001749K.

Technical Context

This device implements a synchronous serial interface with start-bit detection, opcode-driven command set (READ, WRITE, ERASE, ERAL, WRAL, EWEN/EWDS), and internal auto-erase-before-write logic. All operations are initiated by CS high-to-low transition followed by clocked instruction sequences on rising CLK edges.

It uses CMOS nonvolatile floating-gate memory cells with power-on/off protection circuitry that inhibits write access below VCC = 1.5 V. The DO pin serves dual function: serial data output during READ and active-low Ready/Busy indicator during programming - requiring minimum TCSL = 250 ns between instructions.

Key Specifications

Pinout & Package

93LC46A-I/PG is supplied in an 8-lead plastic dual in-line package (PDIP) with matte tin (Pb-free) finish. Pin 1 is marked by laser dot; pin 1 ID corner is bottom-left when notch faces up.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC46B-I/P, the 93LC46A-I/PG offers native 8-bit compatibility and shorter instruction cycles; versus AT25010B-MAHL-T, it preserves legacy Microwire timing and provides hardware-ready signaling - critical for deterministic real-time configuration reads.

Availability

93LC46A-I/PG is available at Aetrix Electronics and suitable for industrial sensor calibration, consumer remote control memory, and automotive body control module applications requiring stable component supply and long-lifecycle support.

Supply support for 93LC46A-I/PG 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 93LC46A-I/PG belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, low-power embedded systems requiring simple, robust, and long-retention nonvolatile storage with minimal pin count.

FAQ

What is the memory organization of the 93LC46A-I/PG?

The 93LC46A-I/PG has a fixed 128 × 8-bit (1 Kbit) organization with no ORG pin - unlike 'C' variants, it does not support x16 mode. This makes it pin- and firmware-compatible with legacy 93C46A devices while offering extended voltage range (2.5–5.5 V) and improved endurance. Its x8 structure simplifies integration with 8-bit microcontrollers using standard Microwire protocols.

Does the 93LC46A-I/PG require an external pull-up resistor on the DO pin?

No, the 93LC46A-I/PG does not require an external pull-up on DO. During READ, DO actively drives data; during READY/BUSSY polling, it outputs active-low status. When CS is low or after status read completion, DO enters High-Z state. However, if DI and DO are shorted (shared bus), a current-limiting resistor (e.g., 10 kΩ) is required to prevent bus conflict during dummy-zero read phase - as documented in DS20001749K Section 2.2.

What is the minimum VCC required to prevent accidental writes on the 93LC46A-I/PG?

The 93LC46A-I/PG incorporates hardware-level power-supply monitoring that inhibits all write operations when VCC falls below approximately 1.5 V - as specified in DS20001749K Table 1-1, Parameter D11 (VPOR). This ensures data integrity during power-up, power-down, or brown-out conditions without requiring external reset supervisors or firmware safeguards.

Can the 93LC46A-I/PG be used in automotive applications?

The 93LC46A-I/PG is rated for Industrial temperature range (–40°C to +85°C), not Automotive (–40°C to +125°C). While it may function in some under-hood environments, Microchip explicitly qualifies only the 'E' suffix variants (e.g., 93LC46A-E/P) for automotive use. For AEC-Q100-compliant designs, engineers must select 93LC46A-E/PG or equivalent qualified parts - the 93LC46A-I/PG is intended for industrial and commercial applications.

How does the ERAL command work on the 93LC46A-I/PG?

The ERAL (Erase All) command on the 93LC46A-I/PG executes a self-timed 6 ms cycle that erases the entire 128-word array to logical '1'. It requires VCC ≥ 4.5 V for reliable operation (per DS20001749K Section 2.5), and automatically precedes WRAL execution. Status is polled via DO pin: low = busy, high = ready. No external timing or address inputs are needed - only the 9-bit ERAL opcode ('10010xxxx') clocked in with CS high.