Loop Powered Transmitter

Hello team,

This is sagar, I have to design Loop Powered Transmitter with TWO 4-20mA output current, 

1st 4-20mA is used to measure Analog signal 1

2nd 4-20mA is used to measure Analog signal 2


Please help me in design circuit or give me block diagram.

Thank you in advance...!!!

  • 0
    •  Analog Employees 
    on Aug 29, 2019 9:24 PM

    Hi Sagar,

    Are the two measurements independent? Current loops support a single transmitter and one or more receivers in. Some transmitters include their own power supply, and a loop-powered transmitter implies that you have a power source elsewhere in the loop.

    Circuit Note 0267 is a good example of a loop powered transmitter. It is based on the AD5421, which has a SPI interface and an internal DAC, while an ADuCM360 digitizes the analog input signal and a temperature sensor. This arrangement allows you to perform temperature compensation and digital calibration.

    If you are looking for a purely analog solution, the AD693 may be an option, or do a parametric search on ADI's 4-20mA drivers:

    https://www.analog.com/en/parametricsearch/11041

    -Mark