Part Number: MAX3232-EP
It was noticed that “V+” was at a correct voltage level when idle, but starts oscillating when a message istransmitted from the module. see following:
The same measurement was done on “V-“, which has a faulty and noisy voltage level when idle, and alsooscillation when a message is being transmitted as noticed on the following capture, furthermore the voltageis incorrect, around -4.75V instead of -5.5V. Significant noise can also be noticed at all times, which is notpresent on a unit with a functional RS-232 transceiver.
If we replace the part the problem disappears.
Has TI some experiences or similar cases already reported for such part, that can indicate some technical issues of the component or wrong usage?
In reply to Wade VonBergen:
yes you understood the issue, the oscillations we see at the output of the components will disappear if we replace the part.
We have many pieces with this issue, if we replace the part with a "good" one we will not see the problem anymore.
In reply to Pietro Zappia:
we had that problem on three different products.
On old two projects:
On recent project :
V+ during TX access (v+ oscillates between 4.31V and 5.54V) with 100nF (recent project) :
V+ zoomed during TX access:
Schematic of recent project:
Has TI been notified of similar issues on that part by other customers?
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