TCA9517: TCA9517 External PULL UP VALUE FOR TCA DISABLE USE CASE

Rajat Singh

Part Number: TCA9517

Hi Team,

We have a use case to Disable the TCA9517.Can you please let us know what will be the right pull-up Value for below schematic.As per my understanding it should be somwhere arround 160K@30uA Leakage current based on

R=VCCB-Enable Pin voltage/leakage current

In our case VCCB is 5V

EN Pin voltage - 0.2 (As per the datasheet)

5-0.2/30uA =160K

I have currently placed 10k as a place holder only.

Please suggest the right value.

Many Thanks

Rajat

10 months ago

0 Jack Guan 10 months ago

TI__Mastermind 28416 points

Hey Rajat,

Yes- this seems correct, the TCA9517 has an internal pullup resistor on the EN pin in the range of 150k~180kohms. This node can be left floating so the device is always enabled, or a pulldown resistor can be used to disable the device (the value of this pulldown should be no greater then 75kohms to ensure VIL threshold of EN pin is met).

Regards,

Jack