PCA9306: SCL/SDA leakage current when unpowered

Michael Balourdas

Expert 5525 points

Part Number: PCA9306

Hello,

If the device is unpowered, what leakage current will there be on the SCL/SDA lines?

Thanks,

Michael

over 4 years ago

0 Clemens Ladisch over 4 years ago

Guru 318050 points

If EN is at 0 V, the switches are off, and you get I_IH.

If a power supply is not at 0 V but floating, EN might be high, and the switches might be (partially) closed.

0 Danny Bacic over 4 years ago

TI__Mastermind 26826 points

Michael,

Clemens is correct. Note that this is effectively the test condition for I_IH:

Since EN should be connected to V_REF2 in application, this is effectively having the device unpowered. You should expect this parameter to apply here.

Best,

Danny

0 Michael Balourdas over 4 years ago in reply to Danny Bacic

TI__Expert 5525 points

Thank you Clemens/Danny. I saw that in the datasheet but wasn't sure if I was interpreting it correctly. I appreciate the clarification.

Michael

0 Michael Balourdas over 4 years ago in reply to Clemens Ladisch

TI__Expert 5525 points

Hi Clemens,

I actually have a follow up question about the floating supplies here.

If the supplies are floating, what is the DC impedance of the SCL/SDA pins?

Thanks,

Michael

0 Clemens Ladisch over 4 years ago in reply to Michael Balourdas

Guru 318050 points

In the worst case, "floating" is the same as "fully powered". (But the current through the 200 kΩ resistor will slowly discharge the supply.)

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PCA9306: SCL/SDA leakage current when unpowered