Microchip Technology 93C46BT-I/OT

Overview

93C46BT-I/OT from Microchip Technology Inc. is a 1Kbit (128 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, operating at 4.5–5.5 V, rated for industrial temperature (−40°C to +85°C), and packaged in SOT-23-6. 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 in embedded system configuration storage and calibration data retention.

For engineers reviewing the 93C46BT-I/OT datasheet, 93C46BT-I/OT pinout, 93C46BT-I/OT application, or 93C46BT-I/OT equivalent, key selection criteria include its fixed 8-bit organization (no ORG pin), SOT-23-6 footprint compatibility, 2 ms program cycle time, 1 million endurance cycles, and support for sequential read and WRAL/ERAL commands under ≥4.5 V supply.

Technical Context

The 93C46BT-I/OT implements a synchronous serial Microwire interface with CS, CLK, and DI/DO pins. It uses a dedicated 8-bit memory organization (no ORG pin function), requiring no external logic for word-size selection. Its internal architecture includes an address decoder, data register, mode decode logic, and output buffer, enabling instruction-based operations including READ, WRITE, ERASE, ERAL, WRAL, EWEN, and EWDS.

Power management is handled by built-in voltage detection (VPOR = 3.8 V), automatic entry into Standby mode when CS is low, and hardware-enforced write protection via EWEN/EWDS commands. All programming cycles are self-timed and initiated by the rising edge of CLK on the final data bit - distinct from 93AA/93LC variants that use CS falling edge initiation.

Key Specifications

Pinout & Package

SOT-23-6 (OT) package: compact 6-pin surface-mount housing with exposed pad option (not connected per datasheet). Pin 1 marked by laser dot; pin 1 = DO, pin 2 = VSS, pin 3 = DI, pin 4 = VCC, pin 5 = CS, pin 6 = CLK. No ORG or NC pins - consistent with 'A' variant designation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93C46B-I/SN, the 93C46BT-I/OT delivers identical functionality in a space-constrained SOT-23-6 package, while AT25010B-SSHL-T requires protocol-level redesign but enables broader voltage operation and higher-speed SPI communication.

Availability

93C46BT-I/OT is available at Aetrix Electronics and suitable for industrial control systems, medical diagnostics equipment, and consumer appliance design requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for 93C46BT-I/OT 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 93C46BT-I/OT belongs to Microchip's legacy 93Cxx serial EEPROM family, designed specifically for cost-sensitive, low-power, nonvolatile data storage in space-constrained industrial and consumer applications using Microwire interfaces.

FAQ

What is the memory organization of the 93C46BT-I/OT?

The 93C46BT-I/OT has a fixed 128 × 8-bit (1Kbit) organization with no ORG pin - it is an 'A' variant device. Unlike 'C' versions, it does not support x16 mode or external word-size selection. This simplifies hardware design by eliminating ORG pull-up/pull-down requirements and guarantees consistent 8-bit data framing for all READ/WRITE operations.

Does the 93C46BT-I/OT support the WRAL (Write All) command?

Yes, the 93C46BT-I/OT supports WRAL, which writes the entire memory array with a single data value. However, WRAL requires VCC ≥4.5 V and the device must first be enabled via EWEN. The command includes an automatic ERAL cycle, so no separate ERAL instruction is needed. Execution time is 15 ms (T_WL) under 4.5–5.5 V conditions.

How is the Ready/Busy status monitored on the 93C46BT-I/OT?

The Ready/Busy status is signaled on the DO pin: logic low indicates ongoing erase/write activity; logic high means completion. To read status, CS must be brought high for ≥250 ns after the programming command, then DO sampled. After status check, issuing a Start bit followed by CS low clears the status flag. DO returns to High-Z when CS is low.

What is the significance of the 'T' and 'I' in 93C46BT-I/OT?

In 93C46BT-I/OT, 'T' denotes the SOT-23-6 package (per Microchip's package code), 'I' specifies Industrial temperature grade (−40°C to +85°C), and 'OT' is the official package identifier per Microchip's documentation. The full suffix confirms it is a Pb-free, matte tin-finished, industrial-grade SOT-23-6 variant of the 93C46B series.

Can the 93C46BT-I/OT be used with a 3.3 V microcontroller system?

No - the 93C46BT-I/OT requires VCC = 4.5–5.5 V and has a 3.8 V power-on reset threshold. It is incompatible with 3.3 V-only systems. For 3.3 V operation, consider the 93LC46B-I/SN (2.5–5.5 V) or 93AA46B-I/SN (1.8–5.5 V), both offering same x8 organization but different voltage ranges and package options.