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