I am working on 3 AD5737 using single SPI communication from MCU. My requirement is that 12 Channels to provide a current output of 4 to 20mA where i should be able to control each channel independently.
AD0=GND AD1=GND for all DAC
MCU MOSI pin to SDI pins of 3 AD5737
MCU CLK pin to SCLK pins of 3 AD5737
MCU CS pin to SYNC pin of 1 AD5737
MCU GPIO1 pin to SYNC pin of 2nd AD5737
MCU GPIO2 pin to SYNC pin of 3rd AD5737
I was able to send data and clock to all AD5737 but only AD5737 provided with CS pin from MCU is responding and other two AD5737 are not responding.
I am controlling GPIO pins in same way as CS pin manually for other two DAC's ,But I am not getting any respond from other two DAC's
I tried following methods:
1. I gave same CS pins to other two DAC's i.e. MCU CS pin is given to SYNC pin of all DAC : I was able to get response from all three but i need to control all channels of 3 DAC individually which is not possible in this method.
2. I gave same CS pins to other two DAC's i.e. MCU CS pin is given to SYNC pin of all DAC and changed AD0 & AD1 pin connection of one DAC as follows
AD0 = GND AD1= Pull up to 5V so device address of one DAC changed to 10 and other DAC retained same address i.e. 00
now if i send SPI data to DAC with address 10 i was able to get response and next if send the SPI data to other DAC with address 00 it is not responding until i turn off the power and turn it on .i.e. i should reset the board when ever i change the address which is not possible to use in real time
Can you please provide me a solution where i should be able to communicate with this 3 DAC's individually and all 12 Channels should work independently.