Microchip Technology 93C46BT-I/MC

Overview

93C46BT-I/MC from Microchip Technology Inc. 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 DFN-8 (2×3 mm) 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 in embedded system configuration storage and calibration data retention.

For engineers reviewing the 93C46BT-I/MC datasheet, 93C46BT-I/MC pinout, 93C46BT-I/MC application, or 93C46BT-I/MC equivalent, key selection considerations include its fixed 8-bit organization (no ORG pin), 2 ms program cycle time, 1 million endurance cycles, 200-year data retention, and compatibility with legacy Microwire controllers in space-constrained industrial modules.

Technical Context

The 93C46BT-I/MC implements a synchronous serial Microwire interface with CS, CLK, and DI/DO lines. It operates exclusively in x8 mode (ORG pin not present), requiring no external configuration logic. All erase/write operations are self-timed and initiated by the rising edge of CLK on the final data bit - a distinguishing timing behavior versus 93AA/93LC variants.

Its internal architecture includes an address decoder, data register, mode decode logic, and output buffer, with built-in power-on reset detection at 3.8 V and hardware write protection via EWEN/EWDS commands. The device enters Standby mode when CS is low, drawing only 1 µA typical ICCS current.

Key Specifications

Pinout & Package

93C46BT-I/MC is housed in an 8-lead 2×3 mm DFN (Dual Flat No-lead) package with exposed pad, Pb-free Matte Tin finish. Pin 1 is marked by laser dot; the exposed pad may be connected to VSS or left floating per Microchip packaging spec.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93C46B-I/MC, the 93C46BT-I/MC offers native 8-bit alignment and simpler address decoding; versus AT25010B-MAHL-T, it delivers deterministic 2 ms write latency and integrated ERAL/WRAL safety - critical for real-time embedded configuration updates.

Availability

93C46BT-I/MC is available at Aetrix Electronics and suitable for industrial PLCs, automotive body control modules, medical infusion pumps, and smart energy meters requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for 93C46BT-I/MC 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 93Cxx family was designed specifically for cost-sensitive, space-constrained embedded systems requiring reliable, low-pin-count serial EEPROM with robust power-supply immunity and long-term data integrity.

FAQ

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

The 93C46BT-I/MC has a fixed 128 × 8-bit (1 Kbit) organization. It belongs to the 'A' variant group within the 93C46 family and does not include an ORG pin - eliminating configuration ambiguity and ensuring consistent byte-oriented access. This differs from 'C' variants that support selectable 8-/16-bit modes via the ORG pin. The 93C46BT-I/MC is fully compatible with legacy 93C46A designs.

Does the 93C46BT-I/MC support the ERAL (Erase All) command?

Yes, the 93C46BT-I/MC supports the ERAL command with a 6 ms typical cycle time. However, ERAL requires VCC ≥ 4.5 V to operate correctly, and the device must first be placed in EWEN (Erase/Write Enable) state. After ERAL completion, the Ready/Busy status is signaled via the DO pin, and issuing a Start bit followed by CS low clears the status. This functionality is identical across all 93C46 variants.

What is the maximum clock frequency supported by the 93C46BT-I/MC?

The 93C46BT-I/MC supports a maximum clock frequency of 3 MHz when VCC is between 4.5 V and 5.5 V. At lower voltages, the maximum frequency decreases: 2 MHz for 2.5 V ≤ VCC < 4.5 V, and 1 MHz for 1.8 V ≤ VCC < 2.5 V. Since the 93C46BT-I/MC operates only within 4.5–5.5 V, its guaranteed maximum FCLK is 3 MHz - enabling high-throughput configuration reads in time-critical boot sequences.

How is write protection implemented on the 93C46BT-I/MC?

Write protection on the 93C46BT-I/MC is implemented through dual hardware mechanisms: (1) Power-on reset lockout below 3.8 V prevents writes during brown-out, and (2) EWEN/EWDS commands control functional enablement. The device powers up in EWDS (Erase/Write Disable) mode; an explicit EWEN instruction is required before any ERASE or WRITE operation. After programming, executing EWDS restores protection. This layered approach ensures robustness against noise-induced or firmware-error writes.

Is the exposed pad on the 93C46BT-I/MC's DFN package required to be connected?

No, the exposed pad on the 93C46BT-I/MC's 8-lead DFN (MC) package may be connected to VSS or left electrically floating, per Microchip's packaging specification. When connected, it improves thermal dissipation and reduces ground impedance; when floating, it maintains full functionality. PCB layout should follow Microchip's recommended land pattern (document DS20001749K, page 26) to ensure mechanical reliability and solder joint integrity.