Microchip Technology 93LC46C-I/MS

Overview

93LC46C-I/MS from Microchip Technology Inc. is a 1 Kbit low-voltage serial EEPROM with Microwire-compatible 3-wire interface, ORG-pin-selectable 8-/16-bit word organization, 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 microcontroller-based systems for storing calibration data, configuration settings, or firmware patches.

For engineers reviewing the 93LC46C-I/MS datasheet, 93LC46C-I/MS pinout, 93LC46C-I/MS application, or 93LC46C-I/MS equivalent, key selection considerations include VCC range (2.5–5.5 V), MSOP-8 package compatibility, ORG-driven memory width selection, Ready/Busy status polling via DO, and timing-critical AC parameters including TWC = 6 ms write cycle and FCLK up to 3 MHz at 4.5–5.5 V.

Technical Context

The 93LC46C-I/MS implements a synchronous serial Microwire interface with CS, CLK, DI, and DO signals, where instruction execution is triggered by a Start condition (CS high + DI high on CLK rising edge). Its dual-word-size capability is controlled solely by the external logic level applied to the ORG pin - VCC selects x16 mode (64 × 16), VSS selects x8 mode (128 × 8).

Internal operation includes automatic pre-erase before WRITE/WRAL, hardware-enforced EWEN/EWDS lockout states, and Ready/Busy status signaled on DO during programming. Power-on reset detects VCC ≥ 1.5 V (93LC variant), enabling reliable initialization without external supervisor circuits.

Key Specifications

Pinout & Package

93LC46C-I/MS is housed in an 8-lead MSOP (Micro Small Outline Package) with 0.65 mm pitch, 3.0 mm × 3.0 mm body, and exposed pad option (not connected per datasheet). Pin 1 is marked by laser dot; package is Pb-free (Matte Tin finish).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC46B-I/MS, the 93LC46C-I/MS adds hardware-configurable word width at no cost in speed or reliability; versus AT25010B-MAHL-T, it preserves Microwire compatibility and offers faster 3 MHz operation at 5 V but requires ORG routing and biasing.

Availability

93LC46C-I/MS is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, medical device configuration, and automotive body control modules requiring stable component supply, long-life data retention, and industrial-temperature operation.

Supply support for 93LC46C-I/MS 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 93LC46C belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, low-power embedded systems needing simple, robust, and field-updatable nonvolatile storage.

FAQ

What is the function of the ORG pin on the 93LC46C-I/MS?

The ORG pin on the 93LC46C-I/MS determines memory word size: tied to VCC, it configures the device as 64 × 16-bit (x16); tied to VSS, it configures as 128 × 8-bit (x8). This pin is not present on A/B variants and must be externally biased - floating is undefined. The 93LC46C-I/MS leverages this pin to provide hardware-selectable interface width without firmware changes.

Does the 93LC46C-I/MS require an external pull-up resistor on the DO pin?

No, the 93LC46C-I/MS does not require an external pull-up on DO. The DO pin actively drives high/low during READ and Ready/Busy status polling, and enters High-Z when inactive. However, if DI and DO are shorted (common-bus configuration), a current-limiting resistor (~1 kΩ) is recommended to prevent bus conflict during the dummy zero phase of READ operations.

What is the minimum VCC required for reliable operation of the 93LC46C-I/MS?

The 93LC46C-I/MS incorporates a power-on reset circuit that inhibits all operations until VCC reaches approximately 1.5 V. Below this threshold, the device remains in a locked state - no writes, reads, or instruction execution occurs. This ensures data integrity during power ramp-up and brown-out conditions without external supervision.

How does the 93LC46C-I/MS handle write protection after power-up?

The 93LC46C-I/MS powers up in Erase/Write Disable (EWDS) mode, blocking all ERASE and WRITE instructions until an explicit EWEN command is issued. This default lockout prevents accidental overwrites during initialization or noise events. An EWDS command should follow each successful write to restore protection - a critical safeguard confirmed in the 93LC46C-I/MS functional description.

Can the 93LC46C-I/MS be used in automotive applications?

The standard 93LC46C-I/MS is rated for Industrial temperature (–40°C to +85°C) and is not qualified for automotive AEC-Q100 stress testing. For automotive use, Microchip specifies the 93LC46C-E/MS variant (–40°C to +125°C), which shares identical pinout, timing, and functionality but undergoes extended qualification. Using 93LC46C-I/MS in under-hood environments risks parametric drift and early failure.