CD4053B: unselected channel has 1.8V voltage

Hello Yang,

Sending a 1.8V signal through the device when the supply voltage is 5V should be fine and not cause issues.

1.Can you tell me the voltage you read on the when using the 1k resistor on as a pulldown. Can your customer try this test with a 50 ohm pull down?

2.Also what is the frequency of the signal your a passing through this device?

3.Is there any chance that the customer put voltage on the io pin before the supply of the mux was turned on?

4.Has the customer seen this error on multiple cd4053 devices?

Please let me know what you think and I can look into this phenomenon more.

Regards,

Kameron

Hi Kameron,

I got some update here.

First, customer tested with 10k pulldown resistor only on the unselected pin 12. Today customer tested with 10k pulldown resistors  on both the selected pin 13 and unselected pin 12. with both pin 12 and 13 have PD resistors, no issue found.

Some test results are shown as below.

2. Frequency is 0 (DC signal, 2.5V or 0V).

3. NO.

4. YES. 100% can be reproduced.

There have amps buffer connected to pin 12 & 13. So, the questions are,

1) if we directly leave the unseleved pin floating without PD resistor,  Does this 1.8V voltage do harm to the device? Why there has 1.8V voltage?

2) Or do you always suggest customer to add the 10k or less PD resistor un both pin 12 & 13?

Thanks.

best regards,

Yang