Microchip Technology 93C46CT-I/MS

Overview

93C46CT-I/MS from Microchip Technology is a 1 Kbit (128 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 4.5–5.5 V supply range, industrial temperature grade (−40°C to +85°C), and MSOP-8 package. It features self-timed erase/write cycles, automatic ERAL before WRAL, power-on/off data protection, and Ready/Busy status signaling via DO pin - used for configuration storage in embedded controllers and sensor calibration modules.

For engineers reviewing the 93C46CT-I/MS datasheet, 93C46CT-I/MS pinout, 93C46CT-I/MS application, or 93C46CT-I/MS equivalent, key selection factors include its fixed 8-bit organization (no ORG pin), 2 ms program cycle time, 1 million erase/write endurance, 200-year data retention, and compatibility with legacy Microwire-based microcontroller peripherals requiring minimal I/O resources.

Technical Context

The 93C46CT-I/MS implements a synchronous serial interface with CS, CLK, and DI/DO pins, operating exclusively in x8 mode (ORG pin not present). Its command set includes READ, WRITE, ERASE, ERAL, WRAL, EWEN, and EWDS - all initiated by a Start bit followed by opcode and address/data on rising CLK edges.

Internal logic enforces power-on write protection: device powers up in EWDS state, requiring explicit EWEN before any programming operation. VCC detection threshold is 3.8 V; below this, all operations are inhibited. Timing-critical parameters - including TWC = 2 ms (93C version), TPD ≤ 400 ns, and TCSL ≥ 250 ns - are guaranteed across the full industrial temperature range.

Key Specifications

Pinout & Package

8-pin MSOP (Micro Small Outline Package), 3.0 mm × 3.0 mm body, 0.65 mm pitch, Pb-free Matte Tin finish. Pin 1 marked by laser dot; pin 1 ID corner located at top-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 93LC46BT-I/MS and AT25010B-MAHL-T, the 93C46CT-I/MS offers deterministic Ready/Busy polling and tighter VCC tolerance for 5 V systems, but lacks low-voltage flexibility and uses a less common Microwire protocol - making it optimal for cost-sensitive, 5 V-only designs with legacy controller support.

Availability

93C46CT-I/MS is available at Aetrix Electronics and suitable for motor control configuration storage, industrial sensor calibration data, and legacy microcontroller peripheral interface applications requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for 93C46CT-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, FPGA, and memory solutions, serving automotive, industrial, consumer, and communications markets with vertically integrated silicon and development tools.

The 93C46CT-I/MS belongs to Microchip's legacy 93Cxx serial EEPROM family, designed specifically for cost-sensitive, low-pin-count embedded systems requiring reliable nonvolatile storage with minimal MCU resource usage and robust power-cycle resilience.

FAQ

What is the memory organization of the 93C46CT-I/MS?

The 93C46CT-I/MS is a fixed 128 × 8-bit (1 Kbit) device with no ORG pin - it operates exclusively in x8 mode. Unlike 'C' variants (e.g., 93C46C), this part does not support x16 configuration. The 'T' suffix denotes tape-and-reel packaging, and 'I/MS' specifies industrial temperature grade in MSOP-8 package. All timing and command behavior align with the 93C-series specification, including 2 ms write cycle and 3.8 V VCC detect threshold.

Does the 93C46CT-I/MS support sequential read operation?

Yes, the 93C46CT-I/MS supports sequential read: after issuing a READ instruction with an initial address, holding CS high allows automatic incrementing through subsequent memory locations, outputting one byte per 8 CLK cycles. This eliminates repeated instruction overhead and reduces total transaction time by up to 40% compared to individual random reads - especially valuable in boot-time configuration loading. The DO pin remains active and stable during the entire sequence.

How is write protection implemented on the 93C46CT-I/MS?

Write protection on the 93C46CT-I/MS is enforced at two levels: hardware and command-based. Hardware protection activates below 3.8 V VCC, disabling all programming functions. Command-based protection requires explicit execution of EWEN before any ERASE or WRITE, and EWDS immediately after to re-disable writes. The device powers up in EWDS state, ensuring no accidental writes occur during power-up unless firmware intentionally enables them.

What is the purpose of the NC pin on the 93C46CT-I/MS MSOP-8 package?

Pin 7 on the 93C46CT-I/MS is designated NC (No Connect) - it has no internal connection and must not be bonded or routed to any signal. Per Microchip's design guidance, it may be left floating or tied to VSS for mechanical stability, but must never be driven or used as a signal path. This pin corresponds to the ORG pin location in 'C' variants (e.g., 93C46C), which is absent in the fixed-x8 93C46A/B series like the 93C46CT-I/MS.

Can the 93C46CT-I/MS be used with a 3.3 V microcontroller system?

No, the 93C46CT-I/MS requires a minimum VCC of 4.5 V and is not rated for 3.3 V operation. Its absolute minimum operating voltage is 4.5 V, and its VCC detect threshold is 3.8 V - meaning it will inhibit all programming below that level and may behave unpredictably at 3.3 V. For 3.3 V systems, consider the 93LC46A/B/C series (2.5–5.5 V) or 93AA46A/B/C series (1.8–5.5 V), both available in MSOP-8 and compatible pinout.