Hello I have a circuit that takes a 4-20mA reading from a pressure transmitter and converts it to analog 0-5V then to I2C. But it doesn't seem to be reading I just see about 0.5V on the serial monitor regardless of if the transmitter is connected to my PCB or not.
So I believe the circuit has an error somewhere, but because it is relatively complicated I am not sure where to begin. The transmitter is connected to the board via screw terminals and has 12V+,12V-, GND connections its current signal is converted to 0-5V using an IC RCV420JP next the analog signal is taken to an ADS1115 ADC which converts the reading to I2C. Because my MCU's logic levels are at 3.3V though I translate the 5V digital readings to 3.3V using a voltage translator TXS0108EPWR. The I2C signals are then sent to the MCU ESP32-WROOM-32UE
I have looked at this a little bit and not been able to spot the error. Does anyone have a clue as to what may be the issue?
Edit Some have suggested that I should connect to both the In- and In+ as I am currently connected to only the In+. I used figure1 and 8 in the RCV420JP datasheet and there doesn't appear to be a connection on In-. After some time, I inquired to Texas Instruments and received a very thorough answer and reference circuit: TI answer