EEPROM Memory IC: Microchip 93LC46BT-I/MS Datasheet and Application Guide

In the realm of non-volatile memory, Serial Electrically Erasable Programmable Read-Only Memory (EEPROM) ICs are fundamental for storing critical data that must be retained when system power is removed. The Microchip 93LC46BT-I/MS stands as a prominent and reliable solution in this category, offering a compact form factor, simple interfacing, and robust performance for a wide array of embedded applications.

This device is a 1K-bit Microwire Serial EEPROM, organized as 64 x 16 or 128 x 8 bits. Its versatility is enhanced by a built-in instruction set that supports both 8-bit and 16-bit organizational modes, which can be selected by the user. Housed in an 8-pin MSOP package, it is ideal for space-constrained PCB designs. The 93LC46BT-I/MS operates over a broad voltage range (2.5V to 5.5V) and supports an extensive temperature range from -40°C to +85°C, making it suitable for industrial, automotive, and consumer applications.

A key feature of this memory IC is its simple 3-wire serial interface (CS, SK, DI, DO), which minimizes the number of I/O pins required from the controlling microcontroller (MCU). This interface, known as Microwire, facilitates easy communication for reading, writing, and erasing data. The device also includes essential functionality for data integrity and protection. It features built-in software and hardware write protection mechanisms to prevent inadvertent writes to the memory array, safeguarding critical parameters. Furthermore, it offers a self-timed write cycle with a typical duration of 4 ms, freeing the MCU from busy-wait loops and improving overall system efficiency.

Typical Applications:

The 93LC46BT-I/MS is ubiquitously used for storing calibration data, configuration settings, and small lookup tables. Common applications include:

Automotive Electronics: Storing odometer data, VIN numbers, and module configuration.

Consumer Electronics: Holding user preferences and setup parameters in devices like televisions, set-top boxes, and audio equipment.

Industrial Systems: Saving calibration constants, device addresses, and operational logs in sensors, PLCs, and meters.

Medical Devices: Retaining critical device settings and usage history.

Design Considerations:

When integrating the 93LC46BT-I/MS, designers must pay close attention to the pull-up resistor on the CS (Chip Select) line to ensure a clean power-on state and prevent unstable operation. Proper decoupling capacitors near the VCC pin are essential for stable performance. Adherence to the timing diagrams detailed in the datasheet for instructions like EWEN (Erase/Write Enable), WRITE, READ, and ERASE is critical for reliable communication. For designs operating in electrically noisy environments, additional measures such as shielding and signal filtering may be necessary to ensure data integrity on the serial lines.

ICGOODFIND Summary:

The Microchip 93LC46BT-I/MS is a highly versatile and dependable 1K-bit serial EEPROM. Its combination of a compact MSOP package, wide voltage operation, simple 3-wire interface, and robust write-protection features makes it an excellent choice for designers needing a small, non-volatile memory solution. Its ease of use and proven reliability have cemented its status as a go-to component across countless industries.

Keywords:

EEPROM, Microwire Interface, Non-volatile Memory, Microchip, Serial Memory