Microchip Technology 93C56AT-I/MNY

Overview

93C56AT-I/MNY from Microchip Technology Inc. is a 2 Kbit (256 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 4.5–5.5 V supply range, and industrial temperature grade (–40°C to +85°C). 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 microcontroller systems.

For engineers reviewing the 93C56AT-I/MNY datasheet, 93C56AT-I/MNY pinout, 93C56AT-I/MNY application, or 93C56AT-I/MNY equivalent, key selection criteria include its dedicated 8-bit organization (no ORG pin), 2 ms typical write cycle time, 1 million endurance cycles, and compatibility with legacy Microwire controllers in space-constrained industrial control modules.

Technical Context

The 93C56AT-I/MNY implements a synchronous serial Microwire interface with CS, CLK, and DI/DO signals. Its internal logic requires a Start bit detection (CS high + DI high on first CLK rising edge) before accepting opcodes. All programming operations - ERASE, WRITE, ERAL, WRAL - are initiated by the rising edge of CLK on the final data bit, distinguishing it from AA/LC variants that use CS falling edge.

It operates exclusively in x8 mode (no ORG pin function), supports sequential read, and enforces hardware-level data protection: VCC must remain ≥4.5 V during ERAL/WRAL, and the device powers up in EWDS (Erase/Write Disable) state, requiring explicit EWEN before any write. Standby current is ≤1 µA at VCC = 5.5 V with CS = 0 V.

Key Specifications

Pinout & Package

93C56AT-I/MNY is supplied in an 8-lead MSOP package (MS) with exposed pad, measuring 3.0 mm × 3.0 mm × 1.0 mm. Pin 1 is marked by laser dot; pin 1 ID corner is 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 93LC56BT-I/MNY, the 93C56AT-I/MNY offers simpler 8-bit byte addressing and direct firmware compatibility; versus AT25020B-MAHL-T, it preserves legacy Microwire infrastructure but lacks multi-voltage flexibility and requires dedicated clock-edge timing handling.

Availability

93C56AT-I/MNY is available at Aetrix Electronics and suitable for industrial motor control, sensor calibration, PLC I/O modules, and legacy controller bootloader storage requiring stable component supply across extended production lifecycles.

Supply support for 93C56AT-I/MNY 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 series was designed specifically for cost-sensitive, low-power industrial and automotive applications requiring robust serial EEPROM with Microwire compatibility and hardware write protection - targeting legacy system upgrades and long-lifecycle deployments.

FAQ

What is the function of the NC pins on the 93C56AT-I/MNY?

The 93C56AT-I/MNY has two NC (No Connect) pins: Pin 6 and Pin 7. These terminals have no internal connection and must be left floating or tied to VSS per PCB layout best practices. They are not used for ORG configuration - unlike 'C' variants, the 'A' version (including 93C56AT-I/MNY) has fixed 8-bit organization and no ORG functionality. Microchip specifies these pins as NC in the official DS21794G datasheet Pin Function Table.

Does the 93C56AT-I/MNY support 3.3 V operation?

No, the 93C56AT-I/MNY does not support 3.3 V operation. Its specified VCC range is strictly 4.5 V to 5.5 V, as confirmed in the Device Selection Table and Electrical Characteristics section of DS21794G. Attempting to operate below 4.5 V risks failure of ERAL and WRAL commands (which require ≥4.5 V) and violates the absolute minimum VCC threshold of 3.8 V for power-on reset detection.

How is the Ready/Busy status monitored on the 93C56AT-I/MNY?

The Ready/Busy status of the 93C56AT-I/MNY is monitored on the DO pin: DO = low indicates ongoing erase/write operation; DO = high indicates completion. To read status, CS must be brought high for ≥250 ns after TCSL, then DO sampled on CLK rising edges. After completion, issuing a Start bit followed by CS low clears the status flag. This behavior is identical across all 93Cxx 'A' and 'B' variants per DS21794G Section 2.4–2.9.

Is the 93C56AT-I/MNY pin-compatible with the 93AA56A or 93LC56A?

Yes, the 93C56AT-I/MNY is pin-compatible with 93AA56A and 93LC56A in the same package (e.g., MSOP), sharing identical 8-pin mapping (CS/CLK/DI/DO/VSS/NC/NC/VCC). However, electrical differences exist: 93C56A requires ≥4.5 V VCC (vs. 1.8–5.5 V for 93AA56A), uses CLK-rising-edge write initiation (vs. CS-falling-edge for 93AA/93LC), and lacks ORG pin support - all confirmed in DS21794G Tables 1-1, 1-2, and Figure 2-2/2-9.

What is the maximum clock frequency supported by the 93C56AT-I/MNY?

The 93C56AT-I/MNY supports a maximum clock frequency of 3 MHz when VCC is 4.5–5.5 V, as specified in Table 1-2 (Param. A1, FCLK). At this rate, minimum clock high/low times are 200 ns/100 ns respectively. Operation above 3 MHz violates AC timing limits and may cause opcode misreads or incomplete data latching - verified in DS21794G-page 4 under "93XX56C only" conditions, which apply to all 93Cxx variants including 93C56AT-I/MNY.