UART Wake up from deep sleep

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long_4668236
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Hi all,

I use Psoc 4100S Plus CY8C4147AZI

I am using uart wake up from deep sleep, when i connect RX with TX FTDI FT232RL USB to serial, the current consumption is 3uA. When i disconnect RX (floating) with TX USB to serial, the current consumption is 2.5mA.

Could you show my mistake?

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Vison_Zhang
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First comment on KBA 750 replies posted 250 sign-ins

The drive mode of uart rx pin is 'digital high-z'. With this drive mode, the input impedance of uart rx pin is >100M Ohm, so it is very easy to couple external noise and trigger silicon wakeup frequently. 

Any digital high-z pin should not be floated if port interrupt is enabled on this pin.

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Vison_Zhang
Moderator
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Moderator
First comment on KBA 750 replies posted 250 sign-ins

The drive mode of uart rx pin is 'digital high-z'. With this drive mode, the input impedance of uart rx pin is >100M Ohm, so it is very easy to couple external noise and trigger silicon wakeup frequently. 

Any digital high-z pin should not be floated if port interrupt is enabled on this pin.