I/O Expanders
I/O expander ICs add additional GPIO (General Purpose Input/Output) pins to microcontrollers via I²C or SPI serial interfaces, enabling expansion of digital inputs and outputs without consuming valuable MCU pins. Available from TI, NXP, Microchip, and onsemi.
Product Series & Base Models
Navigate by model series to compare ordering variants and technical specifications within the I/O Expanders family.
PCA9536DGKR
PCA9536DGKR variants from Texas Instruments
MAX7317ATE
MAX7317ATE variants from Analog Devices
MAX7315AUE
MAX7315AUE variants from Analog Devices
MAX7311AUG
MAX7311AUG variants from Analog Devices
MAX7301AAX
MAX7301AAX variants from Analog Devices
Browse I/O Expanders Products
| PART NUMBER | MANUFACTURER | DESCRIPTION | STOCK | QTY / ACTION |
|---|---|---|---|---|
| PCF8574ANG4 | Texas Instruments | — | 1,228 | |
| PCF8574APWG4 | Texas Instruments | — | 731 | |
| PCF8574APWRE4 | Texas Instruments | — | 699 | |
| PCF8574ADWE4 | Texas Instruments | — | 2,942 | |
| PCF8574ARGYRG4 | Texas Instruments | — | 2,085 | |
| PCF8574ADWRG4 | Texas Instruments | — | 11,424 | |
| PCA9557RGYR | Texas Instruments | — | 43,306 | |
| PCA9557PWT | Texas Instruments | — | 7,305 | |
| PCF8574DGVRG4 | Texas Instruments | — | 783 | |
| PCA9557PW | Texas Instruments | — | 1,817 |
Top I/O Expanders Manufacturers
onsemi
onsemi I/O Expanders products are available for part-number review, stock checks, and RFQ support.
28,226 productsRenesas
Renesas I/O Expanders products are available for part-number review, stock checks, and RFQ support.
74,605 products
NXP Semiconductors
NXP Semiconductors I/O Expanders products are available for part-number review, stock checks, and RFQ support.
20,288 products
Microchip Technology
Microchip Technology I/O Expanders products are available for part-number review, stock checks, and RFQ support.
67,462 products
Texas Instruments
Texas Instruments I/O Expanders products are available for part-number review, stock checks, and RFQ support.
84,045 products
Diodes Incorporated
Diodes Incorporated I/O Expanders products are available for part-number review, stock checks, and RFQ support.
16,703 products
Analog Devices
Analog Devices I/O Expanders products are available for part-number review, stock checks, and RFQ support.
82,970 products
STMicroelectronics
STMicroelectronics I/O Expanders products are available for part-number review, stock checks, and RFQ support.
19,050 productsAbout I/O Expanders
I/O Expander ICs are digital interface components designed to add additional General Purpose Input/Output (GPIO) pins to a microcontroller or microprocessor via a standard serial interface, typically I2C or SPI. By offloading keyboard scanning, LED driving, switch monitoring, and system control pins to a dedicated expander, engineers can select smaller, lower-pin-count microcontrollers, simplifying PCB layout and reducing system cost.
Modern I/O expanders support features like programmable pull-up/pull-down resistors, input state change interrupt outputs (which alert the host MCU only when a change occurs, saving power), integrated PWM engines for LED dimming, and high-current drive capability (up to 25mA per pin). Selection factors include the number of expanded pins (typically 4, 8, 16, or 24), serial interface speed (up to 1MHz or 3.4MHz Fast Mode Plus), operating voltage, and standby current consumption.
Octatronics catalogs a huge selection of I/O expander ICs from market-leading suppliers including NXP Semiconductors, Texas Instruments, Microchip Technology, onsemi, and Diodes Incorporated. Filter by pin count, interface, package, and submit RFQs for volume deliveries.
Frequently Asked Questions
Octatronics can help source a wide range of I/O Expanders from major manufacturers worldwide, including active production parts, long-lead-time items, and hard-to-find components.
Yes. You can submit a single part number or upload a BOM with multiple parts. Our team will check stock, date code, lead time, and pricing for each item.
Availability depends on the specific part number and supplier source. For important orders, buyers can request packaging photos, labels, date code information, and traceability documents.
Yes. Octatronics supports sourcing for active, end-of-life, obsolete, and hard-to-find components through our global supplier network.
Please provide the part number, manufacturer, quantity, required date code, target price, delivery country, and whether original packaging or COC is required.
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