I have a Microchip TC1047A, analog out, SOT23 temperature sensor.
It fails radiated immunity tests at 430 and 150 MHz, and other frequencies.
I have decoupled and filtered it in every possible way.
The only working fix is to shield it.
I have replaced the sensor with two resistors that generate a suitable output.
The susceptibility goes away, so I believe the sensor is RF-sensitive.
Any thoughts?