TCA6418E: Does /INT signal trigger in standby mode(Fscl = 0)?

Hi Marwan,

I recommend using TCA8418E, as this device has same functionality of TCA6418E, but it also has 10-byte FIFO for remember key-event presses. TCA6418E can only process one event at a time. 

Marwan Khalid said:

Regarding TCA6418E:

1 - I would like to ensure that if any of the input changes while the device in standby mode, /INT will trigger?

In other words if FSCL(which is the same is I2C clock) is 0Hz, is the /INT signal affected?

This is dependent on if  the GPIO direction is configured to INPUT through the GPIO_DIR# register (0 = input). 

The interrupt needs to be enabled for the GPIO too through the GPIO_INT_EN register. If this bit is not set, then a state change on the input pin will not trigger an interrupt on /INT. 

Marwan Khalid said:

2 - also is there a similar device that will latch the input so that /INT will only reset upon register read?

So most IO expanders will release the interrupt on /INT if an input goes back to its original state. For example, input changes state from high to low - this event triggers an interrupt. IF the input goes from low back to high, then the interrupt will de-assert. 

TCAL IO expanders can latch the interrupt so that only a register read clears the interrupt. Devices such as TCAL6416 / TCAL9539 have the capability to keep /INT = LOW until the input port register is read regardless if the input goes back to its original state. This functionality is configured through the interrupt latch register 0 / 1. 

Regards,

Tyler

Thanks for your recommendations,

Also I would like to ensure that if a pin is configured as interrupt source, is /INT  triggered even if the device is in standby mode?

Kind regards,

Marwan