This Product Selection Guide contains information to help select products in the I/O Expanders category on DigiKey.com
Devices in this family are used in conjunction with microcontrollers, microprocessors, or similar devices for the purpose of increasing the number of signal connections available for connecting peripheral devices. The typical concept of operation involves the use of serial communications requiring only a few I/O lines on the host device to read/write the status of many input/output pins on the expander device. The technique exchanges speed of communication for increased connectivity and is best suited for applications where fast response is not critical, such as in many human interface applications.
SelectionCharacteristics
DigiKey Programmable: For verified products, DigiKey can program/flash your compiled code or configuration variables prior to shipping. For unverified products, please enquire with ProgCent.Techs@digikey.com.
Number of I/O: Indicates the number of device pins that are capable of being used for general purpose digital input/output functions.
Interface: Indication of which interface(s) or protocol(s) are used by the device to communicate with other components in the system.
Interrupt Output: Indicates whether or not an expander provides an output that allows notifying a controlling device of events such as input state changes.
Features: These are different capabilities or properties of the device such as buzzer outputs or a keypad controller.
Output Type: Indicates what kind of output the device is designed to produce.
Current - Output Source/Sink: The maximum recommended current flow through a device’s output pin. Multiple values reflect ratings that differ depending on direction of current flow.
Clock Frequency: Indicates maximum rated operating frequency of the part.
Voltage - Supply: Typically represented by a range, this indicates the low and high voltage limits which one can expect standard operation. Voltages outside this range may damage the device and other system components.
Operating Temperature: Recommended operating temperature, typically given in a range or as a maximum. Exceeding these temperatures may affect performance or damage the device and other system components.
Mounting Type: Indicates how the device is attached.
Package / Case: Indicates the type of protective case used on an electronic component to allow easy handling, installation, and protection. This selection was determined to be the closest industry standard applicable to the supplier device packaging. Typically it is best to check the actual dimensions from the datasheet rather than depend on this terminology when designing your circuit.
Supplier Device Package: This is what the manufacturer calls the package of this device. They are manufacturer specific. It is typically best to use the actual dimensions from the datasheets rather than to go by this terminology when designing your circuit.
ProductExamples
| MFR PART # | PI4IOE5V6416ZDEX |
|---|---|
| DIGIKEY PART # | PI4IOE5V6416ZDEXDITR-ND - Tape & Reel (TR) |
| MANUFACTURER | Diodes Incorporated |
| DESCRIPTION | IC XPNDR 400KHZ I2C 24TQFN |
| DATASHEET | Click Here |
| MFR PART # | PI4IOE5V6416LEX |
|---|---|
| DIGIKEY PART # | PI4IOE5V6416LEXDITR-ND - Tape & Reel (TR) |
| MANUFACTURER | Diodes Incorporated |
| DESCRIPTION | IC XPNDR 400KHZ I2C 24TSSOP |
| DATASHEET | Click Here |
| MFR PART # | MCP23017-E/SP |
|---|---|
| DIGIKEY PART # | MCP23017-E/SP-ND |
| MANUFACTURER | Microchip Technology |
| DESCRIPTION | IC XPNDR 1.7MHZ I2C 28SDIP |
| DATASHEET | Click Here |
MediaLinks
Articles
IO-Port Expanders Offer Flexibility in MCU Designs
Port Expanders Extend MCU Functionality
I/O Expansion Devices Future-Proof Designs
Serial Converters Enable USB Connectivity
Design Robust Systems for the Industrial IoT
Product Training Modules
Introduction to GPIO Expanders - NXP
GPIO Expanders - Microchip