The Threshold Unit converts the initially analog measurement signals such as the demodulated signal and PID feedback signals into a digital state. A configurable low-pass filter helps to avoid false alarms due to short-lived signal loss or spikes. The digital signals can be combined using Boolean functions such as AND, OR & XOR. This allows the simple set-up of complex logical frameworks which can reject signals that do not meet required criteria. This functionality is available on all MFLI and MFIA instruments, simply by upgrading to the latest version of LabOne.
The MFLI Lock-in amplifier with Quad-PID controller is a powerful instrument for SPM applications. For FM-KPFM applications, the Modulation Option can output modulated amplitude and frequency signals and demodulate the incoming measurement signal. The Threshold Unit can be used to monitor the scanning feedback signal and trigger a threshold-dependent output to maintain safe boundaries. Acting in this Tip-Protection role, the Threshold Unit reliably prevents tip crashes and keeps valuable tips sharp.
Visit Zurich Instruments at www.zhinst.com