MCP23xxx hardware address pins internal resistors

Projects Networking, Protocols, and Devices
1

Hi,

I'd like to know whether the hardware address pins on MCP23008, MCP23017, MCP23S08 and MCP23S17 are pulled up to VDD, pulled down to VSS or left floating. I want to use a SPST DIP switch to control the hardware address. Should I use external pull-up resistors?

Thanks in advance,
anustart

2

What's their spec say? Probably that input pins should not be left floating. I'd go with pullups, and switch to Gnd when low is desired. No switching 3.3V or 5V on & off to pins.
Up to 0.5mA from a 10K to +5V is likely sufficient for a CMOS input. Since it's static input, can be even less - 20K, 25K.