XTR116: current limit issue

Driscoll Tsai

Part Number: XTR116

Hi Sir,

Pls reference below circuit, this circuit is work normally and the output voltage (VRL)= 5V (20mA*250ohm). If I swinging the Micro-USB cable, the voltage will increase to 7V and will latch till re-plugin this cable.

I think it may over current protect but don't know how to happen. I also confirm the supply voltage is above 7.5V, you can reference waveform. Could you tall me how to resolve?

thanks~

Regards,

Driscoll

over 5 years ago

0 kai klaas69 over 5 years ago

Guru 140200 points

Hi Driscoll,

I think it has to do with what we have discussed here:

e2e.ti.com/.../770353

Kai

0 Luis Chioye over 5 years ago in reply to kai klaas69

TI__Mastermind 49455 points

HI Driscoll,

The XTR116 is a 2-wire transmitter, and all the driving circuitry (sensor and driving amplifiers/circuits) must be fully powered between the XTR116 regulator (VREG) and/or the XTR116 reference (VREF) and referred to the XTR116 IRET. The current consumption of the complete sensor/driving circuit has to be below 4mA.

Please refer to the blog below:

IV. 2-Wire 4-20mA – Controlling 2-Wire Transmitters with Externally Powered Sources

https://e2e.ti.com/blogs_/b/precisionhub/archive/2015/02/24/two-wire-4-20ma-transmitters-background-and-common-issues-part-4

Thank you and Regards,

Luis

Also below, find other 2-wire transmitter topics you will find useful:

I. 2-Wire 4-20mA Sensor Transmitters: Background + Compliance Voltage

https://e2e.ti.com/blogs_/b/precisionhub/archive/2014/11/04/two-wire-4-20-ma-transmitters-background-and-common-issues

II. 2-Wire 4-20mA – IRET Can’t connect to Vloop GND

https://e2e.ti.com/blogs_/b/precisionhub/archive/2014/12/09/part-2-two-wire-4-20-ma-transmitters-background-and-common-issues

III. 2-Wire 4-20mA – IRET < 4mA

https://e2e.ti.com/blogs_/b/precisionhub/archive/2015/01/13/two-wire-4-20ma-transmitters-background-and-common-issues-part-3