TCA9509DGKR-TI Vs PCA9509DP,118-NXP

[Rajvan123]

Hi Team,

One of my top customer is considering PCA9509/P(NXP) in place of TCA0509. Based on the datasheet analysis and spec I decided to use NXP as an alternate without doing any current design modification. I have attached the current schematics. During testing the NXP part, I see some differences during the initial power condition. SCLK on both A and B sides try to oscillate, whereas the same circuit TI part performance is very clean and the ramp-up time is very sharp. . The EN pin is tied directly to the 5V supply. 

Any help would be very helpful. 

Please see the Schematics and Screenshots:

[guoweisun]

Can you decrease the pull up resistors of IIC to try again?

[Rajvan123]

My apologies for the delayed response. I tried lowing the pull-up resistor and tested it up to 2K value which didn't improve the initial hiccups. 

Do you want me to go further down and see what happens?

[guoweisun]

For this part the work condition:

Operating supply voltage range of 0.8 V to 2.0 V on port A, 2.3 V to 5.5 V on port B

[Rajvan123]

On the PCA9509DP :

Operating supply voltage range of 1.35 V to VCC(B) - 1.0 V on port A, 3.0 V to 5.5 V on
port B