The previous three parts of this blog series focused on 2-wire 4-20mA sensor transmitter designs composed completely of analog components. While analog signal conditioning is practical for linear sensors, many sensors have nonlinear outputs that can only…
Part 2 of this blog series derived the basic transfer function for a typical 2-wire transmitter, commonly used in industrial control and automation, and explained the currents flowing inside it. It also explained that connecting the transmitter return…
Part 1 of this blog series provided an overview of the operation and uses of 2-wire 4-20 mA field sensor transmitters and provided a basic example system. The post also introduced the current transmitter compliance voltage, which when violated prevents…
Part 1:
2-wire 4-20 mA sensor transmitters are very common in industrial control and automation. They are popular because they allow a remote process to be monitored with only two analog signal wires. The two wires carry both the power for the sensor…
thank you so much for reply.....................
i mix analog and digital ground only at one point near xtr116 ic i have used in my ckt.i also want to generate 4-20 transmitter so i used xtr116 ic and for that i mix both ground near its iret pin otherwise…
Chip XTR116 I will use als 2-wire current electronic for Draw-wire displacement sensors. I tried chip XTR101, this solution was very good, but I search chiper solution and I select XTR116. Draw-wire displacement sensor have measuring range 1m, this is…
Hello,
This will not work as you've drawn it as you are improperly using the optocouplers. There is a full schematic provided in the design you sent, have you tried implementing circuitry that more closely resembles the one shown in the design?
Notice…
Hello Magne,
I'm not with TI; I'm just another engineer who's used the XTR116, done EMC, etc.
A couple of questions and considerations:
Your ACPL-C87A seems to have a differential outout voltage. Can it be connected single-ended?
If not, I…
I have 3 wire strain gauge sensor. And I want to transmit this signal through 4-20mA current loop using XTR115.
So kindly guide me with this.
Thank you.
Hello Thales,
We have a few comments on your circuit.
First, since you're not utilzing the "VREF" function of the XTR116 we suggest you take a look at the XTR117 which does not include the VREF output.
Second, it's recommended to add an…
Hello Magne,
Kris pointed something out that I missed the first time which is that the ACPL-C87A output is differential. I'm a little concerned that you have a fundamental grounding issue present on the input side of the XTR116 because I don't see how…
Hello,
Please confirm that the "Multi" values are measured at the node between R4 and RIN referenced to IRET, not between Vref and IREF as stated in your post.
It concerns me that you weren't able to make measurements with a scope because of…
I'm sorry. I can not share all of the Company for that project. How do I make these measurements otherwise withoutan external DAC ?(with xtr116). I would like to add a circuit to measure the current in the load. Thankk u for interest.
In my application I found a problem. There were pulses on the load (few volts peak-to-peak and about 3 kHz frequency). When I found in the datasheet information about Vref output capacitive load limitations I removed 10 uF capacitor from this output and…
Hello Collin,
Sorry for being late on this.
1) No I need to 1 MCU Control for 1 XTR116. I'm using control with PWM. (ADC)
2) I used to PNP Transistor for MCU and XTR116 connection. I've only just pot normally use, without MCU.
3) I'm using the…
Hi,
I think I can use teh XTR115, it seems one of the best transmitters.
But I need to improve the temperature stability; drift.
As far I have calculated the device is for a 100 degrees temperature drift
typical…
Hi Collin,
Sorry for being late on the updates.
I have developed a PCB for the discussed system as per your suggestions.
My system requires 3.3V for microcontroller which I have taken from Vreg pin of XTR116 following two dioded in series. I have also…
Hello,
I would like to work with a device that allows 3 or 4-wire connection. Are there any possibilities to use that transmitter with this configuration?
Thanks in advance.
Juliana Campos
First, since you're not utilzing the "VREF" function of the XTR116 we suggest you take a look at the XTR117 which does not include the VREF output.
Couldn't find the XTR117 in Brazil so I tried with XTR116 that I found on local Farnell…
Hello,
I have the same concerns with this design as I did with the design in the link below:
http://e2e.ti.com/support/amplifiers/precision_amplifiers/f/14/p/376041/1327970.aspx#1327970
If you want to use an MCU/DAC that is not powered from the VREG/IRET…
Hello Richard,
The XTR110 is a 3-wire transmitter, so it must receive power from a dedicated supply pin instead of from a 4-20mA loop. This is optimal for the part's intended application, which is converting voltage input signals from a DAC or microcontroller…
