TCA9803: TCA9803 power off A side high impedance

Yunjing Wang1

Part Number: TCA9803

Tool/software:

Hi team,

My customer is using TCA9803, and wondering what is the impedance value when A side is power off? Could you pls share the impedance value in this case? Thank you!

Powered-off high impedance I 2C bus pins on Aside

Thanks!

Yunjing

3 months ago

0 Michael Ikwuyum 3 months ago

TI__Mastermind 32875 points

Hi Yunjing,

High impedance, typically in the M ohms range, thanks.

Best Regards,

Michael.

0 Yunjing Wang1 3 months ago in reply to Michael Ikwuyum

TI__Expert 3360 points

Hi Michael,

Thanks for your reply! Do you have more specific number for the impedance range?

Customer requires larger than 2MR so that they can keep the leakage current below 1.8uA when TCA9803 is powered off but the remote link device still have 3.3V signal connected to this pin, it’s a requirement for HDMI CEC signal, we use this for CEC signal level shift.

Thank you!

0 Tyler Townsend 3 months ago in reply to Yunjing Wang1

TI__Mastermind 31353 points

Hi Yunjing,

Checking this in lab today. I'll get back to you hopefully by eod with resistance measurement.

Regards,

Tyler

0 Tyler Townsend 3 months ago in reply to Tyler Townsend

TI__Mastermind 31353 points

Hi Yunjing,

Resistance from VCCA to GND measures >10Mohm

Regards,

Tyler

0 Yunjing Wang1 3 months ago in reply to Tyler Townsend

TI__Expert 3360 points

Tyler,

Appreciate your support here! Just quick confirmation, >10MR do you mean by VCCA to GND? Or I2C pins at A side to GND?

What we asked is A side I2C pins to GND.

Thank you!

Yunjing

0 Michael Ikwuyum 3 months ago in reply to Yunjing Wang1

TI__Mastermind 32875 points

Hi Yunjing,

I measured 6.5 Mohms at A side to GND, thanks.

Best Regards,

Michael.

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TCA9803: TCA9803 power off A side high impedance