TPS25750: I2C_IRQ and OVP

Hi  Hideki-san

Hideki Hayashi1 said:

1. What is the IRQ main function? When is it triggered?

I assume here you are talking about the I2Cs-IRQ pin on the TPS25750? (not the slave one)

In general, the IRQ pin is used to indicate to an I2C master that the I2C slave has something it needs checked.

In the case of the TPS25750, it works similarly. There are many events that can trigger the interrupt(ie. ErrorMessageData, or ErrorPowerEventOccured). When one of those events occurs, it will assert within the INT_EVENT register (0x14). Within the INT_MASK register(0x16) you can choose which events actually trigger the IRQ pin and disable ones that you do not want triggering the pin.

The IRQ pin will be asserted(triggered) when an interrupt event occurs and that event is turned on in the interrupt mask.

When the interrupt pin triggers, the Host will be indicated that an Interrupt event has occurred, but will not know which one occurred(all events trigger the same pin). The Host on the I2C line must read the INT_EVENT register over I2C to determine which event occurred, and use that information to take any actions that may need to occur. After the interrupt has been "handled"(how it is handled is up to the customer), the interrupt needs to be cleared in the INT_CLEARX Register.

Hideki Hayashi1 said:

2. Is the OVP setting able to react to the contract voltage? For examplse, a negotiation is 9V, OVP threshold will be 11V, a negotiation is 20V, OVP threshold will be 24V.

Yes.