{"title":"Adafruit PCA9546 4-Channel I2C Multiplexer","handle":"adafruit-pca9546-4-channel-i2c-multiplexer","url":"/products/adafruit-pca9546-4-channel-i2c-multiplexer","description":"Need to use multiple I2C devices that share the same address? The PCA9546 4-Channel I2C Multiplexer lets you connect up to four same-address I2C devices to a single microcontroller by acting as a gatekeeper — write a single byte to select the active channel and all subsequent I2C traffic is routed to that port.\n\nThe multiplexer sits at I2C address 0x70 (adjustable from 0x70 to 0x77 via solder jumpers). With eight possible multiplexer addresses, you could theoretically control up to 8 × 4 = 32 same-address devices on one I2C bus.\n\nKey Features\n\n\n4 Multiplexed I2C Channels – Route I2C traffic to any of four downstream buses\n\nSimple Control – Write a single byte to select the active channel; all further I2C packets go to that port\n\nConfigurable Address – Default 0x70, adjustable to 0x70–0x77 for up to 8 multiplexers on one bus\n\n3 V and 5 V Compatible – Works with any logic level\n\nSTEMMA QT / Qwiic Connectors – Solderless I2C connection on the upstream side\n\nBreadboard Friendly – Breakout PCB with capacitors, pull-ups, and pull-downs included\n\n\nHow It Works\nThe PCA9546 acts as an I2C switch. Your microcontroller sends a command byte to the multiplexer's address (0x70 by default) specifying which downstream channel to activate. All subsequent I2C communication passes through to the selected channel. You can enable multiple channels simultaneously if needed.\n\nIdeal For\n\nUsing multiple identical I2C sensors (same address) on one bus\nIsolating I2C bus segments to avoid address conflicts\nExpanding I2C capacity on address-limited projects\nSensor arrays and multi-sensor data logging\n\n\nPackage Contents\n\n1× Adafruit PCA9546 4-Channel I2C Multiplexer breakout, assembled\n\n\n\nNote: Header pins, STEMMA QT cables, and I2C devices are not included. Some soldering required for breadboard use.\n\n\nResources\n\n\nWhat is STEMMA QT? – Introduction to the STEMMA QT connector system\n","vendor":"Adafruit","product_type":"physical","in_stock":true,"options":[],"variants":[{"id":1815,"title":"Default Title","sku":"AF-5663","price":7.71,"on_sale":false,"in_stock":true,"available_quantity":100,"option1":"Default Title"}]}