This is for an Automotive upcoming project.
TIC12400 interface has a filtering stage at its input side. Could you please help with value of resistor used in filter.
Hi Sobin,
The supply current will depend on how the device is configured and also how much current is being sourced through external switches. The device will consume some current to power the internal circuits, but the majority of the current will flow out through the INx switches that are closed to GND.
There are two wetting current modes the device can be configured for, Continuous Mode and Polling Mode.
In continuous mode, the wetting current source circuits are not disabled while the device is triggered and any closed switch will cause current to flow for the duration of time the switch is closed. To calculate the supply current in this mode, you simply add the current consumed by the device in the Idle state which is when there are no active INx pins, to the amount of wetting current times the number of switches closed.
In Polling Mode, the wetting current is turned on for a period of time needed to sample the INx pins, and then it is disabled for the remainder of the cycle. Both the cycle time, and the time the current is active can be configured to different values. Also, the wetting current level and the state of the switch add additional variables that need to be factored into the calculation.
The good news is that we have some tools designed for this purpose. The TIC12400EVM-KIT has a free GUI that can be downloaded and used even without an EVM connected to the PC. It has a Polling Mode Calculator tool that calculates the current for your specific configuration.
There is also an excel spreadsheet version of the tool you can find in this other E2E link.
Regards,
Jonathan
