CD4053B: Switches & multiplexers - INTERNAL forum

Hello Kelly,

Our switches and muxes are essentially a FET that opens to let the signal through or is closed to stop the signal from passing. However, this case is only true in an ideal world. In reality, these switches have parasitic components and will add loss. 

In your case it is either drain or source and there are two paths for it to "leak" through to the other side. 

Thanks,

Nir 

Hi Nir,

Thank you for your reply. I still have two questions here:

1. For a 10M Ohm load, I think 10 nA leakage current is needed to induce a 1V voltage at the pin. Under what test condition can leakage current reach this level?

2. Does the leakage current come from the input current or the system supply?

Thank you for your time!

Best Regards,

Kelly

Hello Kelly 

1. Leakage current can increase with temperature, or when the devices behavior is faulty. I am not sure exactly what is the case here. You mentioned: "According to your previous answer, the voltage at the unselected pin is due to the leakage current". Can you please link the thread of where the answer was posted for more context about your issue?

2. There is current leakage from any signal going into the mux. The leakage itself comes from the FETs inside the mux. 

Thanks,

Nir 

Hi Nir,

Thank you for your reply! Here is the previous thread link: https://e2e.ti.com/support/switches-multiplexers-group/switches-multiplexers/f/switches-multiplexers-forum/1386889/cd4053b-unselected-channel-has-1-8v-voltage/5310678#5310678

Best Regards,

Kelly