A thermal management for EMI shielded circuit packs having one or more high-power components, i. The comparator also has a buffer unit, providing an output signal according to a first input signal and the reference voltage; wherein the voltage generator provides the reference voltage according to a second input signal, and the output signal represents a compare result of the first and second input signals. The collimator traverses the shield from the compact neutron generator to a collimator port. The contributions are equalized for output signal values at more than a saturating distance above the reference signal, and the contributions are equalized for output signal values at more than the saturating distance below the reference signal.