Your cart is empty.
Your cart is empty.You just found the perfect I2C sensor, and you want to wire up two or three or more of them to your Arduino when you realize "Uh oh, this chip has a fixed I2C address, and from what I know about I2C, you cannot have two devices with the same address on the same SDA/SCL pins!" Are you out of luck? You would be, if you didn't have this ultra-cool TCA9548A 1-to-8 I2C multiplexer! Finally, a way to get up to 8 same-address I2C devices hooked up to one microcontroller - this multiplexer acts as a gatekeeper, shuttling the commands to the selected set of I2C pins with your command. Using it is fairly straight-forward: the multiplexer itself is on I2C address 0x70 (but can be adjusted from 0x70 to 0x77) and you simply write a single byte with the desired multiplexed output number to that port, and bam - any future I2C packets will get sent to that port. In theory, you could have 8 of these multiplexers on each of 0x70-0x77 addresses in order to control 64 of the same-I2C-addressed-part. Like all Adafruit breakouts, we put this nice chip on a breakout for you so you can use it on a breadboard with capacitors, and pullups and pulldowns to make usage a snap. Some header is required and once soldered in you can plug it into a solderless-breadboard. The chip itself is 3V and 5V compliant so you can use it with any logic level.
Mr. B
2025-09-02 18:16:55
I built this device into a complex Hammond organ MIDI project that has 12 MCP23017 port expanders on four I2C busses. This I2C mux let’s one Arduino Mega handle all the the traffic via its single I2C hardware ports. I’m handling interrupts across the four busses (through the TCA9548A) at up to 100 per second when driven by a simulated organ player. That’s far more than needed in my application.
HAL 9000
2025-08-23 09:16:34
I started putting together a quad copter with six TOF sensors and unfortunately found out the addresses weren't assignable after they came in. I bought this multiplexer and was using all of them, along with a BPM280 and MPU6050 through it in no time.
Aaron
2025-08-04 18:24:50
not or uno r4::long story short -- the mux works great with uno board, but wont do more than scan ports connected to an uno r4 / wont route your i2c through to peripherals.long story -- i thought the mux was working with my uno r4 wifi board because i could scan ports and see connected i2c device hex id, but could not get my i2c comm to get through the mux and to peripheral device... wasted so much time questioning myself. then before giving up hope, i randomly connected an old uno board and IT WORK with nothing changed... i've read there being various issues with wire.h with uno r4, but the displays and devices worked just fine connected directly to the uno r4, just not through the mux...
Dan
2025-06-12 18:58:47
Replaced 5 of the other company's product that didn't work!
Eye Pod
2025-06-02 15:25:10
Another quality product from Adafruit.It worked according to specs. I am confident it would still be working if I hadn’t accidentally misconnected something else in the circuit.
I. P. Freely
2025-03-23 12:23:53
I missed the return window by just a few days on this. This item cannot be connected to from my Mega 2560. I downloaded the appropriate Adafruit library and when I scan the multiplexer, the only message that appears is the dreaded "Cannot connect to Multiplexer" error. SDC and SDA connections are all correct, the mux is connected to the 3v and GND on the Arduino, the RTC and all other items power is drawn from a separate 5v rail.I'll have to try again on this. This is the first time that Adafruit has let me down.
nate
2025-03-15 11:58:40
We've used this in a product and use it when testing/prototyping. I've even created an open source .NET library for the LibFt232h chip it uses, and then several others for specific sensors connected through this chip.
SERGIO TORRES
2025-01-13 16:42:37
A+++
Recommended Products
$10.99
$ 5 .99 $5.99