My ADM3251 Is sending random values. I am using EVAL-ADM3251EEBZ for testing the ADM3251 for RS232 communication. I am using particle electron for sending data and at the other hand I am using serial monitor for monitoring the communication via USB to TTL converter. I am giving 5V as a input and also separate 5V to Viso. When I directly read the data from particle it is giving me correct data however when I send it through eval board it is not getting detected or reading the true value. Can you guide me through the process?
If Vcc is 5V, the integrated DC-DC converter is enabled meaning Viso should not be powered externally. You only need to power Viso externally if the voltage applied to Vcc is within the 3V to…
Apologies for the delayed response.
I would expect no issues with this, as the data rates are quite low.
This could cause signal integrity issues for example, if the data rates involved were…
If Vcc is 5V, the integrated DC-DC converter is enabled meaning Viso should not be powered externally. You only need to power Viso externally if the voltage applied to Vcc is within the 3V to 3.7V range, as the integrated DC-DC converter will be disabled.
From my interpretation, it sounds as if you are powering Vcc with 5V and powering Viso externally with 5V?
You can find the Vcc and Viso pin descriptions in Table.8 of the datasheet which explain this, and you can reference Figure 14 from the datasheet which shows a typical operating circuit with the DC-DC converter enabled. Note that Viso pin should not be used to power external circuitry.
There's also a user guide you can follow which will step you through the process of setting up the evaluation board:
Let me know if this solves your issue or if it persists,
Thanks for the clarification. I replaced my connections and it is working ok now. Thanks for the assistance.
I have one more question regarding the usage of the RS232 cable. Can I eliminate the DB9 connector and directly solder my wire for serial communication? Does it have any cons?
This could cause signal integrity issues for example, if the data rates involved were much higher.
That helps a lot, I appreciate it.