By the way: whats the difference between the two I/O expanders? The RESET functionality? Or would it be possible to use just two PCA9538PW/Q900,118 as it’s possible to set the hardware address?
It might just be that easy… The reset of the registers look the same. The address would be 0x71 unless you lift pin 1 and GND it. Or change the layout…
hmm… the PCA9554APW,118 is available for assembly now… It doesn’t have a reset and it has internal pullups on the I/O’s which will draw a little more power… I’m not sure if the reset is necessary?
Do I want to have the part pre assembled or self source the PCA9538 and solder it myself!! decisions, decisions…
After looking at it further… We would have to hook VDD to 3.3V. This would limit the external io connections to drive to 3.3V only. If those have to drive to 5V then a translator would be needed.
For me that’s fine. I don’t think I need them to be 5V? I think I’ll make it so with some population options, either part (the original or the PCA) can be used…
For Searching a replacement of the TCA6408AQPWRQ1take into account that this specific device has two separated supply circuits for IO and communication.
Allows Bidirectional Voltage-Level Translation and
GPIO Expansion Between 1.8-, 2.5-, and 3.3-V I2C Bus and P-Ports
In the past we had a wrong type on the controller that could only handle 3v3 on the IO side while it was connected to 5v.
Unless I"m missing something… Digikey has stock for PCA6408APW.118
and Newark has stock for both [PCA6408APW,118] and [PCA9534APWR]
PCA9554A should also work for PCA9534A… It just has internal pullups on the i/o’s and will
burn more power when pulled low…
I just received my JLCPCB order of the ESP32 Controller Board. It was missing a couple parts C3, C4 Tantalum Capacitors, the relays, as well the TCA9534A. I ordered off eBay from the UK the TCA9534A. Im praying they are legit. The company looked to have pretty good reviews. Here’s the link if anyone is interested. They are $5/GBP not exactly cheap but I figured I would try this before the Chinese fakes/empty box.
By the way does anyone have a good replacement for C3,C4 Tantalum Capacitors? The LCSC part number off the BOM doesn’t even come up with anything.
Just received the TCA9534A TSSOP16 from Lanka Electronics ( http://www.lankamicro.com) - Chip is working and doing its job!
They were about $3,80 each, shipment via China Post EUB $7 and customs again about $7… It took about 5 weeks or so…