Part Number: ISO7241M
I m using ISO7241M in my design,
Output waveform of the isolator is DC shifted. Its not reaching Zero volts.
Below is the Schematics and output waveform.
Digital isolator Schematic:
To better understand the system and issue, please share below details
In reply to Tejas Hommaradi:
In reply to Sujay Arasegowda:
Thanks for the information.
In the scope waveform attached, I assume the digital isolator output is measured at Sensor_SIN and the input is measured at DO_PH. Please correct me if my understanding wrong. If yes, are there other nodes on this line and is there any pull up resistor on this line? Is it possible to disconnect the isolator output being routed to MCU/ADCS7476 and capture the output waveform at the IC pin. This will help us to understand if the DC offset is introduced by ISO7241. Regards Tejas
You are right, Output is measure at Sensor_SIN (Blue waveform) and input measured at DO_PH (Pink waveform)
This line doesn't have any pull-ups.
Is it possible to disconnect the isolator output being routed to MCU/ADCS7476 and capture the output waveform at the IC pin. This will help us to understand if the DC offset is introduced by ISO7241 --->As there are no jumpers connected between the outputs and inputs of the isolator, it would be difficult to isolate the output. We will try for it.
Please let me know if you have any suggestions.
We have tested the ISO7421 seperately (isolating it from controller)
Made external circuit with ISO7421M and provided inputs as below
Input (pin 11) :Connected to Isolated Ground, i.e Low
EN1 /EN2 : Checked both Open and High
Output Pin: 6: (monitored w.r.t DGND , output side ground) ; Measured 4.09 V
But as per datasheet for Low Input, output should also be Low-
We were unable to get the output as mentioned in datasheet for IN=L then OUT=L.
Require your help on this.
This is NOT expected behavior from our device. The ICs are extensively tested before shipping out. Can you please redo the previous experiment with a fresh IC.
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