SigOFIT optically insulated fibre optic voltage probes
The Micsig SigOFIT series is a state-of-the-art range of optically isolated probes specifically designed for precise measurements in high-frequency and high-voltage applications. These probes utilize Micsig's exclusive SigOFIT™ technology to deliver exceptional performance in terms of common-mode rejection ratio (CMRR) and isolation voltage. With a bandwidth of up to 1 GHz and a CMRR of up to 180 dB at DC and 108 dB at 1 GHz, SigOFIT probes are ideally suited for the precise measurement of differential signals in the presence of large common-mode voltages. Key Features and Functions: Optical Isolation Technology: SigOFIT probes utilize fiber optic connections to ensure complete galvanic isolation between the measuring instrument (such as an oscilloscope) and the test circuit. This enables safe measurements in high-voltage environments while minimizing the risk of common-mode voltage interference.
Wide range of applications: The SigOFIT series probes are versatile and suitable for applications including the development of motor drives, power converters, electronic ballasts, and the analysis of GaN and SiC semiconductor devices. They are also ideal for safety testing in high-voltage and high-frequency applications.
High precision: With a DC gain accuracy of 1% and noise suppression of less than 450 µV RMS, SigOFIT probes offer extremely high measurement accuracy. This enables the precise acquisition and analysis of even the smallest signal details.
Versatile Attenuation Tips:The SigOFIT series probes are available with various attenuation tips, offering attenuation ratios from 10:1 to 10,000:1. This allows them to measure a wide range of differential voltages from ±0.01 V to ±8000 V. Furthermore, the probe's gain function can amplify the signal by a factor of 10, providing two attenuation ranges for each attenuation tip. However, it should be noted that when using the gain function, interference and noise may also be amplified.
Fast calibration and easy handling: The SigOFIT probes have an automatic calibration function that is completed in less than one second and can be performed without disconnecting the test circuit. This ensures efficient and easy handling, especially for repeated measurements.
Robust and compact design:Despite their advanced technology, SigOFIT probes are compact and robust, making them suitable for use in both laboratories and demanding industrial environments.
Overall, the SigOFIT series has been developed with the highest safety standards in mind to provide users with a safe and reliable measurement environment, especially when working in high-voltage and high-frequency environments. These safety features make SigOFIT probes an excellent choice for demanding and hazardous measurement applications.
Wide range of applications: The SigOFIT series probes are versatile and suitable for applications including the development of motor drives, power converters, electronic ballasts, and the analysis of GaN and SiC semiconductor devices. They are also ideal for safety testing in high-voltage and high-frequency applications.
High precision: With a DC gain accuracy of 1% and noise suppression of less than 450 µV RMS, SigOFIT probes offer extremely high measurement accuracy. This enables the precise acquisition and analysis of even the smallest signal details.
Versatile Attenuation Tips:The SigOFIT series probes are available with various attenuation tips, offering attenuation ratios from 10:1 to 10,000:1. This allows them to measure a wide range of differential voltages from ±0.01 V to ±8000 V. Furthermore, the probe's gain function can amplify the signal by a factor of 10, providing two attenuation ranges for each attenuation tip. However, it should be noted that when using the gain function, interference and noise may also be amplified.
Fast calibration and easy handling: The SigOFIT probes have an automatic calibration function that is completed in less than one second and can be performed without disconnecting the test circuit. This ensures efficient and easy handling, especially for repeated measurements.
Robust and compact design:Despite their advanced technology, SigOFIT probes are compact and robust, making them suitable for use in both laboratories and demanding industrial environments.
Overall, the SigOFIT series has been developed with the highest safety standards in mind to provide users with a safe and reliable measurement environment, especially when working in high-voltage and high-frequency environments. These safety features make SigOFIT probes an excellent choice for demanding and hazardous measurement applications.
More detailed information about the features can be found on the respective product model page

Series overview
| Model comparison | ![]() MOIP200P | ![]() MOIP350P | ![]() MOIP500P | ![]() MOIP1000P |
|---|---|---|---|---|
| Bandwidth | 200 MHz | 350 MHz | 500 MHz | 1GHz |
| Rise time | ≤1.75 ns | ≤1ns | ≤700 HP | ≤350 HP |
| SMA input impedance | 1MΩ; || 10pF | 1MΩ; || 10pF | 1MΩ; || 10pF | 1MΩ; || 10pF |
| Output voltage | ±1,25V | ±0,5V | ±0,5V | ±0,5V |
| Differential voltage range | 1X: ±1.25V 2X: ±2.5V 10X: ±12.5V 20X: ±25V 50X: ±62.5V 500X: ±625V1000X: ±1250V 2000X: ±2500V 5000X: ±6250V
| 1X: ±1.25 V 2X: ±2.5V 10X: ±12.5V 20X: ±25V 50X: ±62.5V 500X: ±625 V1000X: ±1250V 2000X: ±2500V 5000X: ±6250V | 1X: ±0.5V 2X: ±1V 10X: ±5V 20X: ±10V 50X: ±25V 500X: ±250 V1000X: ±500V 2000X: ±1000V 5000X: ±2500V 1000X: ±5000V | 1X: ±0.5V 2X: ±1V 10X: ±5V 20X: ±10V 50X: ±25V 500X: ±250V1000X: ±500V 2000X: ±1000V 5000X: ±2500V 1000X: ±5000V |
| Noise | <450μVrms | <450μVrms | <450μVrms | <450μVrms |
| Propagation delay | 15.42 ns (2 m cable length) | 15.42 ns (2 m cable length) | 15.42 ns (2 m cable length) | 15.42 ns (2 m cable length) |
| Power supply | USB type-C, DC: 5 V | USB Type-C, DC: 5 V | USB Type-C, DC: 5 V | USB Type-C, DC: 5 V |
| DC amplification accuracy | 1 % | 1 % | 1 % | 1 % |
| Common mode voltage range | 60kVpk | 60kVpk | 60kVpk | 60kVpk |
| Cable length | 2 M (Std.) (customisable) | 2 M (Std.) (customisable) | 2 M (Std.) (customisable) | 2 M (Std.) (customisable) |
MOIP1000P
SigOFIT MOIP1000P fibre optic probe The SigOFIT MOIP1000P (MOIP10P) optically isolated probe allows the measurement of fast switching voltages at 1 GHz.
€16,999.00*
MOIP200P
SigOFIT MOIP200P Glass fibre probe The SigOFIT MOIP200P (MOIP02P) optically isolated probe allows the measurement of fast switching voltages at 200 MHz.
€2,999.00*
MOIP350P
SigOFIT MOIP350P Glass fibre probe The SigOFIT MOIP350P (MOIP03P) optically isolated probe allows the measurement of fast switching voltages at 350 MHz.
€4,999.00*
MOIP500P
SigOFIT MOIP500P Glass fibre probe The SigOFIT MOIP500P (MOIP05P) optically isolated probe allows the measurement of fast switching voltages at 500 MHz.
€8,999.00*






