Getting Started With Serial EEPROMs
Serial EEPROM Overview
Our serial EEPROM products are compatible with five serial bus types and support densities that range from 128 bits up to 4 Mbits. These bus types include the standard two-wire I2C, three-wire Microwire, four-wire SPI, along with proprietary single-wire and UNI/O buses. With operating voltages ranging from 1.5V up to 5.5V and operating temperature ranging from -40°C to 150°C, they can support almost all applications. Our EEPROMs are alsotriple tested before they are shipped to provide exceptional endurance for your application.
We continue to offer new serial EEPROM innovations. Our single-wire devices require just one I/O pin to interface with a microcontroller or another single-wire chip. These are ideal for adding verification, usage record and counterfeit protection to your devices. Additionally, we offer a family of MAC address chips, each of which is pre-programmed with unique EUI-48™ and EUI-64™ node addresses. We also manufacture Unique ID EEPROMs that are pre-programmed with a 32-, 48-, 64- or 128-bit serial number to provide device identification and tracking.
What is EEPROM?
This short three-minute video will give you a high-level overview of EEPROM including what it is, why it sells, when to choose it and when not to choose it.
How to Select Your Serial EEPROM
When choosing a serial EEPROM, there is a balancing act between cost and density, but the system software will usually drive this requirement. Usually the amount of memory required to complete a project is estimated before the design is completed. The final density purchased is usually 50% larger to allow for future growth.
To better illustrate the process of selecting a specific EEPROM device, here is an example of the types of questions that come up in the design phase:
- Does the microcontroller have a programmable serial port that can support I2C, SPI, Microwire or UNI/O® serial buses?
- How many spare I/O ports on the microcontroller are available for use by the EEPROM?
- Is your microcontroller pin limited?
- Is it cheaper to switch to a bigger microcontroller or reduce the I/O ports required to interface with the serial EEPROM?
- Do you need to use less I/O pins with memory on the microcontroller to free up the extra I/O pins for other applications?
- Are there any other peripherals in the system design that use a serial interface such as I2C, SPI or Microwire?
- If no serial ports are available, will the serial interface be emulated by bit banging several I/O ports?
- How much memory will be required to complete the project and will it be necessary to upgrade to a larger memory size in the future?
- If more memory is needed, will a larger package impact the design?
- If more memory is needed will cascading serial EEPROMs be a viable option
- Is the bus speed known so that a bus type can be selected?
- If there is a limitation of I/O ports, will the slower speeds of the I2C or UNI/O bus meet the system requirements since they use the fewest I/O ports, two and one respectively?
- Are there any space constraints in the application that dictate a smaller package or die/wafer?
- Is there a minimum or maximum voltage or operating temperature requirement?
In many cases, the application notes and technical briefs you read will point you directly to the part you should use. Finally, contact your contact our local Microchip representative and discuss your findings with one of our knowledgeable sales staff or Field Applications Engineers (FAEs). They would be happy to help you with your Serial EEPROM selection.
Microchip University Memory-Related Coursework
Strategies for Nonvolatile MemoryReliability
This class covers how EEPROM and NOR Flash memory operate, wear out and fail, as well as several strategies for maximizing performance and reliability of memory devices in applications.
Practical I2C: Introduction, Implementation and Troubleshooting
This class covers how to implement the I2C protocol on 8-bit PIC® microcontrollers (MCUs) using MPLAB® Code Configurator (MCC).
NVRAM and EEPROM Selection andDesign
This class is an overview of external nonvolatile memories. We will discuss the different types, how they operate and why some can wear out and discuss some of the tradeoffs between the various types in applications where they fit best.
I2C Serial EEPROM Products by Density
SPI Serial EEPROM Products by Density
Microwire Serial EEPROM Products by Density
UNI/O Bus Serial EEPROM Products by Density
Single-Wire Serial EEPROM Products by Density
Pre-Programmed MAC Address and Unique ID EEPROMs
Need a MAC address but don’t want to buy in bulk? Or do you maybe need a generic unique ID? Microchip makes serialization easy with pre-programmed EEPROMs including IEEE EUI-48™ and EUI-64™ addresses and unique 32-bit and 128-bit Microchip-defined serial numbers.
Tiny Four-Ball WLCSP EEPROMs
Do you have a space-constrained application? Or are you looking to integrate EEPROM memory into your module? These tiny four-ball Wafer Level Chip Scale Package (WLCSP) EEPROMs will fit on the tip of your pen. They are ideal for applications where tiny matters, including smartphones, high-frequency cable ends, cameras, handheld and medical devices. Advanced features like software write protection and configurable hardware addressing allow full I2C functionality while only requiring four physical connections.
Single-Wire and UNI/O Bus EEPROMs
Want to learn more about our innovative communication buses that use just one pin to interface with a microcontroller (MCU)? Discover how to reduce the number of pins needed for your design with our single-wire and UNI/O Bus EEPROMs.
DIMM-DDR2/DDR3/DDR4 EEPROMs
We offer JEDEC-compliant Serial Presence Detect (SPD) EEPROMs for use in DRAM Dual Inline Memory Modules (DIMM). These include software write protection features for the lower 128 bytes of the EEPROM that can be made permanent.
Serial EEPROM PIM PICtail™ Pack
Part Number: AC243003
The Serial EEPROM PIM PICtail Modules are a series of boards designed around Microchip serial EEPROM devices. The boards are designed to interface with the PICtail Plus connector as well as the MPLAB® Starter Kit for Serial Memory Products and the PICkit™ 4 programmer/debugger, allowing you to get started right out of the box.
Serial Memory SPI Evaluation Kit
Part Number: EV20F92A
This evaluation kit is an easy-to-use interactive user tool that demonstrates the best-in-class features, functionality and low-power operation of our SPI serial EEPROM devices. The included Graphical User Interface (GUI) makes it easy for you to configure and evaluate SPI serial EEPROMs, shortening the overall development time needed to bring new designs from prototype to production.
Serial Memory I2C Evaluation Kit
Part Number: DM160237
This evaluation kit is an easy-to-use interactive user tool that demonstrates the best-in-class features, functionality and low-power operation of our I2C serial EEPROM devices. The included Graphical User Interface (GUI) makes it easy for you to configure and evaluate I2C serial EEPROMs, shortening the overall development time needed to bring new designs from prototype to production.
- Brochures
- Reference Manual
| Serial EEPROM | Parallel EEPROM | OTP EPROM | Serial Flash | Parallel Flash | Serial SRAM | Serial NVSRAM | Serial EERAM | |
|---|---|---|---|---|---|---|---|---|
| Explore Products | Explore Products | Explore Products | Explore Products | Explore Products | Explore Products | Explore Products | Explore Products | |
| Density | 128 bit - 4 Mb | 64 Kb - 1 Mb | 256 Kb - 8 Mb | 512 Kb - 64 Mb | 1 - 64 Mb | 64 Kb - 1 Mb | 512 Kb - 1 Mb | 4 Kb - 1 Mb |
| Clock Frequency | 0.4 - 20 MHz | 70 ns | 45 ns | 20 - 104 MHz | 55-70 ns | 16 - 20 MHz | 16 - 20 MHz | 1 - 66 MHz |
| Cost/Bit | High | High | High | Low | Low | Medium | Medium | Medium |
| Read Times | Medium | Fast | Fast | Medium | Fast | Medium | Medium | Medium |
| Write Times | Medium | Fast | N/A | Medium | Fast | Instantaneous | Instantaneous | Instantaneous |
| Pin Count | 2 to 8 pins | 28 and 32 pins | 28 to 44 pins | 8 pins | 32 and 48 pins | 8 pins | 8 pins | 8 pins |
| Data Retention | 200+ Years | 10 Years | 10 Years | 100+ Years | 100+ Years | Volatile | 20+ Years (with battery) | 100+ Years |
| Typ. Standby Current | 1 µA | 200 µA | 100 µA | ~15 µA | ~30 µA | ~4 µA | ~4 µA | ~40 µA |
| Voltage | 1.7 V - 5.5V | 2.7V, 5V | 2.7V, 5V | 1.65V - 1.95V, 2.7V - 3.6V, 2.3V - 3.6V | 1.65V - 1.95V, 2.7V - 3.6V, 4.5V - 5.5V | 1.65V - 1.95V, 2.5V - 5.5V | 2.5V - 5.5V | 2.7V - 3.6V, 4.5V - 5.5V |
| Temperature | -55°C to +150°C 1 | -55°C to +125°C | -40°C to +85°C | -40°C to +125°C 1 | -40°C to +85°C | -40°C to +125°C | -40°C to +85°C | -40°C to +125°C 1 |
1. Selected densities