Microchip Technology 93C46C-I/SN

Overview

93C46C-I/SN from Microchip Technology Inc. is a 1 Kbit (128 × 8 or 64 × 16) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, ORG pin for runtime word-size selection, and industrial temperature range (−40°C to +85°C). It supports self-timed erase/write cycles, automatic ERAL/WRAL, and Ready/Busy status via DO pin. Used in embedded system configuration storage, sensor calibration data retention, and firmware parameter backup.

For engineers reviewing the 93C46C-I/SN datasheet, 93C46C-I/SN pinout, 93C46C-I/SN application, or 93C46C-I/SN equivalent, key selection criteria include V_CC range (4.5–5.5 V), 8-/16-bit configurable organization, 1 million endurance cycles, 200-year data retention, and SOIC-8 package compatibility with legacy board layouts.

Technical Context

The 93C46C-I/SN implements a synchronous serial Microwire interface with CS, CLK, DI, and DO signals, where instruction execution begins on a Start condition (CS high + DI high at CLK rising edge). Its dual-organization memory array (128 × 8 or 64 × 16) is selected dynamically by the logic level on the ORG pin-tied to V_CC for x16 mode or V_SS for x8 mode.

Internal control logic enforces power-on write protection: V_CC must exceed 3.8 V for reliable operation, and the device powers up in EWDS (Erase/Write Disable) state. All erase/write operations require prior EWEN command, and status polling is performed via DO pin after minimum TCSL (250 ns CS low time), with DO = 0 indicating busy and DO = 1 indicating ready.

Key Specifications

Pinout & Package

93C46C-I/SN is packaged in 8-lead SOIC (SN), with lead finish Matte Tin (Pb-free). Pin 1 is CS, Pin 2 is CLK, Pin 3 is DI, Pin 4 is DO, Pin 5 is V_SS, Pin 6 is ORG (functional - selects 8-/16-bit mode), Pin 7 is NC (no internal connection), and Pin 8 is V_CC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC46C-I/SN and AT25010B-MAHL-T, the 93C46C-I/SN provides deterministic 5 V operation and hardware-configurable word width - critical for legacy industrial controllers using 5 V logic and variable data-width peripherals.

Availability

93C46C-I/SN is available at Aetrix Electronics and suitable for industrial automation, automotive electronics, medical instrumentation, and consumer appliance design requiring stable component supply and long-lifecycle support.

Supply support for 93C46C-I/SN 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 microcontroller, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design, manufacturing, and sales operations.

The 93Cxx series was designed specifically for cost-sensitive, low-power serial EEPROM applications in industrial and automotive environments where reliability, wide temperature operation, and Microwire compatibility are essential.

FAQ

What is the function of the ORG pin on the 93C46C-I/SN?

The ORG pin on the 93C46C-I/SN selects memory organization: tied to V_CC, it configures the device as 64 × 16 (x16 mode); tied to V_SS, it configures as 128 × 8 (x8 mode). This pin is functional only on 'C' variants like the 93C46C-I/SN and is NC on 'A'/'B' versions. Proper biasing is mandatory - floating ORG causes undefined behavior. The 93C46C-I/SN uses this pin to maintain backward compatibility with both 8-bit and 16-bit host interfaces without redesign.

Does the 93C46C-I/SN support 3.3 V operation?

No, the 93C46C-I/SN does not support 3.3 V operation. Its specified V_CC range is strictly 4.5 V to 5.5 V, and its power-on reset threshold is ~3.8 V. Attempting to operate below 4.5 V risks unreliable communication, incomplete writes, or data corruption. For 3.3 V systems, consider the 93LC46C-I/SN (2.5–5.5 V) or 93AA46C-I/SN (1.8–5.5 V), which share identical pinout and ORG functionality but differ in voltage specifications. The 93C46C-I/SN is optimized for legacy 5 V designs.

How do I read the Ready/Busy status from the 93C46C-I/SN?

To read Ready/Busy status from the 93C46C-I/SN, first ensure CS has been low for ≥250 ns (TCSL), then bring CS high while maintaining CLK and DI stable. The DO pin will output low (0) during active erase/write cycles and high (1) when complete. Status polling must occur after the falling edge of CS initiates the operation and before the next instruction. The 93C46C-I/SN does not support status read during CS low - DO remains High-Z in that state. Always clear status post-operation by issuing a Start bit followed by CS low.

What is the maximum clock frequency supported by the 93C46C-I/SN?

At V_CC = 4.5–5.5 V, the 93C46C-I/SN supports a maximum clock frequency of 3 MHz (per Table 1-2, A1). This applies to all instructions - READ, WRITE, ERASE, ERAL, and WRAL. Clock timing margins (TCKH ≥ 200 ns, TCKL ≥ 100 ns) must also be met. Exceeding 3 MHz risks setup/hold violations, especially on DI and DO, leading to opcode misreads or corrupted data. The 93C46C-I/SN's 3 MHz limit reflects its 5 V CMOS process optimization - lower-voltage variants like 93LC46C reduce max frequency to 2 MHz at 2.5–3.0 V.

Can the 93C46C-I/SN be used in automotive applications?

The 93C46C-I/SN 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-dash locations, Microchip does not qualify or guarantee performance beyond +85°C. For automotive applications requiring AEC-Q100 compliance or extended temperature operation, use the 93C46C-E/SN (E-temp grade), which shares identical functionality and pinout but is tested to +125°C. The 93C46C-I/SN is appropriate for industrial control panels, HVAC systems, and commercial equipment where ambient temperatures remain within its specified range.