Unlike traditional differential probes can only test high-voltage signals, Micsig’s SigOFIT probes can be used with various attenuator tips to test differential mode signals from ±1V to ±2500V, achieving full-range output and very high signal-to-noise ratio.

Saelig Company, Inc. has introduced the Micsig SigOFIT Series Opto-isolated Probes which have excellent amplitude/frequency characteristics, and deliver an excellent common mode rejection ratio (CMRR up to 112dB at 100MHz, over 100dB at 500MHz.) The full-range noise floor is 1.1mVrms max, and the 24-hour zero drift is less than 50uV.  These SigOFIT probes feature Micsig’s exclusive SigOFIT ™ optical isolation technology, remotely powered by laser light or battery, offering extremely high isolation voltage to help engineers to see true, uncorrupted signals within their specified bandwidths.

Five bandwidth models are available for signals from 100Hz to 1GHz, with the measurement heads either battery-powered or opto-isolated LED laser-powered.  The input test leads of the SigOFIT probes are short and have coaxial cables for transmission from the measurement heads.  They present less than 3pF input capacitance load, which makes these probes ideal for testing SiC and GaN devices that can switch high voltages in a few nanoseconds, and produce very high-energy high-frequency harmonics. Unlike traditional differential probes which can only test high-voltage signals, the SigOFIT series probes can be used with different attenuator tips to test differential mode signals from ±1V to ±2500V, achieving full-range output and very high signal-to-noise ratio.  Smaller in size than traditional differential probes, and with more precise probe tips, SigOFIT isolated probes are easier and more versatile to use than conventional differential probes. With very fast response, signals can be tested immediately after power-on, with no need to wait for a warm-up period. Autozeroing in less than 1 second insures accurate signal measurements in real time.  Even at the highest bandwidth, the SigOFIT probes still have approximately 100dB CMRR to perfectly suppress oscillations caused by high-frequency common-mode noise.

Applications include:

• Design of motor drive, power converter, electronic ballast
• Design & analysis of GaN, SiC, IGBT Half/Full bridge devices
• Design of inverter, UPS and switching power supply
• Safety test for high voltage, high bandwidth applications
• Power device evaluation
• Current shunt measurements
• EMI & ESD troubleshooting
• Floating measurements

The Micsig SigOFIT Series of opto-isolated oscilloscope probes are the best choice for accurate third-generation semiconductor test and measurement tasks.  Made by Shenzhen-based Micsig, a leading provider of battery-powered portable and handheld oscilloscopes since 2004, SigOFIT probes are available now from Saelig Company Inc., Micsig’s authorized North American distributor.