ISO1212: VCC1 is given 5V but output given is 2V

Chee Yong Tan

Part Number: ISO1212

Hi,

I am running out of idea as to what is wrong with my design. I have design a custom board with ISO1212 and TXB0108PWR to an MCU as shown below. When I input a 12V using DC signal generator and measure the voltage between OUT1 and GND, it gives me 2V (VCC1 = 5V). What could be causing this?

over 4 years ago

0 Koteshwar Rao over 4 years ago

TI__Guru 53025 points

Hi Chee Yong Tan,

Sorry to hear about the issue. I am not quite sure why do you see 2V at OUT1 when VCC1 is 5V, maybe there is something wrong somewhere else. Could please share schematic so that I can review?

If the decoupling caps are not placed right then it is possible for the device to behave abnormal. Please do share the schematic and PCB layout for review, thanks.

Regards,
Koteshwar Rao

0 Koteshwar Rao over 4 years ago in reply to Koteshwar Rao

TI__Guru 53025 points

Hi Chee Yong Tan,

Please do share the above information requested so that I can take a look at to see if there are any issues. Thanks.

Regards,
Koteshwar Rao

0 Koteshwar Rao over 4 years ago in reply to Koteshwar Rao

TI__Guru 53025 points

Hi Chee Yong Tan,

I have not heard from you in a while. I hope you were able to identify the cause for the issue and fixed it accordingly. I will go ahead and mark this closed but if you think your issue is still not resolved then please do respond to the post to continue to the discussion. If this post gets locked out and you can't reply then please do create a new related post. Thanks.

Regards,
Koteshwar Rao

0 Chee Yong Tan over 4 years ago in reply to Koteshwar Rao

Prodigy 45 points

Hi Koteshwar,

Yes I was able to resolve the issue. Thank you.

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ISO1212: VCC1 is given 5V but output given is 2V