Interfacing AD9833 with TCA9548A

i want to interface two DDS-AD9833A with Arduino , but it is having only one set of SDA/SCL.
with single board it is working good. now i want to interface two DDS-AD9833A boards.
now i want to use TCA9548A, to interface two AD9833 for two channel.
when i connect the first AD9833A with SDA0/SCL0....i cant get the wavesignal from it, meanwhile it is showing 0 values.
please help me how to interface two AD9833A with TCA9548.
thanks in advance


Did you read and try the tutorial from Adafruit about how to do this? Overview | Adafruit TCA9548A 1-to-8 I2C Multiplexer Breakout | Adafruit Learning System

Hi, @anjulatha
I didn't quite understand your difficulty.
AD9833 does not use the I2C interface (SDA/SCL).
It uses the SPI interface.

"3-wire SPI interface"
I believe that using TCA9548A will not solve your problem.

The AD9833 has a standard serial interface that allows the part to
interface directly with several microprocessors. The device uses
an external serial clock to write the data or control information
into the device. The serial clock can have a frequency of 40 MHz
maximum. The serial clock can be continuous, or it can idle high
or low between write operations. When data or control information is written to the AD9833, FSYNC is taken low and is held
low until the 16 bits of data are written into the AD9833. The
FSYNC signal frames the 16 bits of information that are loaded
into the AD9833.

RV mineirin

Like @ruilviana says, AD9833 uses SPI, not I2C interface. If you have free Arduino pins, it may be easiest to simply manage two AD9833 boards with different pins - for example, one with hardware SPI and the other with software SPI.

Hi, @anjulatha
Welcome to the forum.

If you google

arduino spi two devices

It will show you tutorial on how to interface more than one device on the SPI bus.
You do not have to use a mutliplexer.

Tom... :smiley: :+1: :coffee: :australia:

Thank you for reply.
ad9833 working on SPI , using MISO,MOSI,SCK....
but it is using only MOSI as SDA, and sck as sck.. as in I2C. no connection for MISO....

we can interface, AD9833 with SDA(A4)and SCL (A5).and it is working, we checked the waveform.

my problem is ...can we interface two AD9833 with I2C bridge...TCA9548.?

sorry if any mistakes


Can you change the I2C address of the 9833?
Read the data sheet.
If you can, you do not need the I2C bridge.

Tom... :smiley: :+1: :coffee: :australia:

That is NOT an I2C device. If you are using the library mentioned in reply #4, then your code will define which 3 pins you use to talk to the ad9833. You can have multiple instances using different pins...

Maybe post your code?