!)I want to use AD7124_8 for universal analog input. So that I can connect channel number RTD or TC or 4-20mA or 0-10V.Is that possible with Ad7124_8?
2) AD7124 ADC 8 channel differential input is there so that can use channel one for RTD application, Channel two for Thermocouple application,channel three for 4-20mA application, and channel four 0-10v application. So is that possible to configure like this way in AD7124_8?
1 ) The EVAL-AD7124-8-PMDZ board is good.but my problem that how to configure universal analog input schismatic to this board. especially if I want first channel all input like rtd,4-20mA,0-10v, and…
I believe yes it will definitely possible. Especially the RTD and TC inputs as most of the building blocks needed for this type of sensors are already integrated on the chip. We have a reference circuit that will help you start with the design of TC with RTD as its cold junction. Please see below reference circuit.
For the 4-20mA and 0-10V inputs, this will require an external shunt for the current input and attenuator divider for the voltage input.
We also have available AD411x family that will also suit your application.
AD4111/AD4112 are capable of measuring direct 0 to 10V and 4-20mA inputs without the need of any external circuitry. You can use this along with AD7124-4 for your universal input module.
We also have AD4110-1 that allows all inputs above in a single ADC. However, if you require 4 channels I think an external Mux will be needed here.
Please see also all available resources that you may find helpful.
Also, you can take a look at the CN0414 reference design.
Yes am using the example code which your providing the link (CN0391) and my hardware also similar.
Yes, I will start with a simple code to ensure my communication.
Can you share with me any sample code for reading back the id register or Writing a register and reading back the register for confirmation. That will be great helpful to me.
The input voltage and output voltage of ad7124-8 are attached below please have a look.
If you have an ADICUP3029 around you can use this code/application https://github.com/analogdevicesinc/EVAL-ADICUP3029/tree/master/projects/ADuCM3029_demo_ad7124_8PMDZ to read AD7124-8 registers.
Am using an Atmega328p microcontroller ( Arduino UNO).
In terms of the code, If you are using the example code for CN0391 I would suggest to ask this with the SDG team or MihaiS team as they may have better understanding how the code works.
You can ask this through Reference Circuit Community As someone there may also have a similar question.
We have example code here that should work with any microcontroller. You can use this as a reference. I think there's a function there that shows how to write and read to a certain register. Again, if you have any specific query regarding the code itself, someone from the No-OS drivers community can assist you.
Then once you fixed your code and confirm proper communication with the device, you can come back in this thread to discuss the part itself and the application side.
I posted in the reference circuit community.
In my hardware am not using an external reference pin(12&13 PIN ) and SYNC_N pin also. am not separating analog-digital ground and power supply.is this will affect communication?.
There's no issues with Pin12,13 or SYNC pin left unconnected. I think it is also fine to have single analog and digital plane if you are not operating in a harsh environment. But I would recommend to have at least a separate supply for AVDD and IOVDD as digital section should be a bit noisy and could affect your analog measurements. But in terms of communication point of view, I don't think it has a big impact. However, in the attached schematic I noticed that you used different symbols, can you clarify that both AGND and DGND and MCU GND at some point are externally connected?
Another suggestion is to at least check the MCU first with a scope if it is outputting what you desired to write to the ADC before connecting it to the daughter board. This is just to know if the issue is with the code or MCU itself or when you tried to connect them with your daughter board.
Your hardware setup should not affect communication as the IOVCC is the same as VCC, probably 3.3V in your case. Probably your setup is the same as EVAL-AD7124-8-PMDZ so check out this schematic: https://wiki.analog.com/resources/eval/user-guides/circuits-from-the-lab/eval-ad7124-8-pmdz#schematic_pcb_layout_bill_of_materials
To verify that the communication is working you can simply try to read the ID register and then check the rest of the registers. If your reading is incorrect, one reason may be the reference selection in the setup, or the reference is not enabled.
When am comparing my hardware and EVAL-AD7124-8-PMDZ both are almost the same. For my hardware, I added some RTD and thermocouples circuits is added apart from I think both are the same.
For your reference am attaching my schismatics please have a check.
Can you share with me the sample code for the reading ID register?.
5047.SCHEMATIC1 - PAGE5.tif
From your schematic, I see that you are using for some analog signals, the digital ground, and for other the analog ground. You will need to use digital ground only for digital signals and analog ground for analog signals and then connect these two grounds together through a ferrite bead to reduce the injected noise from the digital section to the analog one.
Or you can use a single ground.
One of my colleagues will help you with the sample code.
Now am using single ground by shorting digital and analog ground. and made some changes in my hardware as per CN0391 hardware. Still am facing the same issue.
If you can share the code it will be geat helpful to me.