I'm designing a PCB that will have two PCF8574 ICs each with their own unique address connected to an Atmel 328P on the I2C bus. The circuit will be operating at 5V with between 3-4Amps. The datasheet for the PCF8574:
This shows the pullup resistors for SDA, SCL and INT connections, each 10k. How do I calculate the correct resistor values to use as pullups for SDA, SCL and INT, or will 10k pullup resistors be sufficient?