High Voltage Optically Isolated Probe - FireFly® Series
■ Ideal for GaN / SiC high-side VGS measurements
■ Best-in-class >1.5GHz bandwidth, <300ps rise time
■ Industry-leading ultra-low temperature drift of < 0.05%/°C
■ >180dB CMRR from DC to 500kHz, 80dB at 1GHz
■ ±60kV common mode voltage
■ Wide range of differential input voltage tips
■ Quiet operation, no fan
■ Complete galvanic isolation
■ Universal BNC interface - Use with any oscilloscope
The FireFly® high voltage optically isolated probe offers industry leading performance that combines the ability to accurately resolve high bandwidth, small differential signals in the presence of large common mode voltages with its ultra-high common mode rejection performance across its entire bandwidth. With >1.5GHz bandwidth, wide differential input range, unmatched common mode rejection ratio CMRR up to >180dB (1 billion to 1 rejection), and a 60kV common mode, FireFly® is the ideal measurement solution for both GaN and SiC device characterization and system level design development.
PMK‘s optically isolated interface and unique compact angled probe head design are the key attributes that set FireFly® apart from the other solutions in the market, providing very stable and accurate measurements over a wide temperature range and easy access to the measurement points in tight spaces.
The compact angled probe head design allows for shorter tip cables to be used, resulting in higher signal fidelity measurements and reduced stresses placed on the measurement test point. FireFly®‘s wide selection of probe tip connections and accessories offer reliable, hands-free, high-fidelity connectivity to the measurement points. Using industry standard MMCX and square pins connections allow FireFly® to easily interface to test boards that have already been design with these test points.
FireFly® has a universal BNC output connector and is compatible with any oscilloscope with a 50Ω input impedance or 1MΩ input impedance and a 50Ω feed-through termination, allowing FireFly® to be used on any oscilloscope in the lab.
For accurate deskew, each probe‘s unique propagation delay is measured and added to each probe label.
The FireFly® probe head is powered by an easy to change, rechargeable, industry standard 18650 battery that provides continuous operation for up to 30h at room temperature. The interface box is powered by the required PMK power supply. The 2ch PS2 and 4ch PS3 power supplies all have remote control capabilities and therefore a USB interface and optional additional LAN interface. As an alternative for most flexible use, the 1 channel battery pack power supply AP-01 provides >8h of portable and isolated operation but has no software remote control.
FireFly® series has the capability to be controlled from either remote control or the controls located on the interface box.
FireFly® Series’ DC offset can be controlled via remote control.
A PMK power supply unit is required. These are available with a USB interface and are optionally available with a LAN interface. Remote control of the probe is made possible by the power supply unit.
The exact range of functions of the probes is described on the page linked below for the respective software solution.
Several software solutions are available for remote control of PMK products:
https://www.pmk.de/en/remotecontrol
ISO17025 calibration upon delivery or as re-calibration is possible on request.
Customer Testimonials
"In our solid-state circuit breaker research, the PMK FireFly probe delivers outstanding insulation capability and high-bandwidth performance, allowing precise measurement of high-voltage spikes and ultra-fast SiC MOSFET turn-off currents."
FireFly® System Overview: Setup and Key Components
A typical FireFly® test and measurement setup includes:
- the FireFly® system,
- an (external) FireFly® power supply, and
- an (external) oscilloscope.
The oscilloscope and the power supply are connected directly to the grid.
The FireFly® system itself consists of:
- a 'floating' probe head,
- a 'grounded' interface box (IB), and
- a fiber-optic cable.
Probe head and IB are permanently connected through the fiber-optic cable—forming an inseparable assembly.
The FireFly® system interfaces with the oscilloscope and power supply via its IB. A BNC connector links the IB to the oscilloscope for signal transmission, while a Lemo-type connector connects it to an external power supply. The IB also serves as a control unit, providing features like "auto-zero," status indicators, and more. It establishes a ground connection through its BNC port, while the fiber-optic cable output and all downstream components (red lines) remain fully galvanically isolated, ensuring interference-free, high-fidelity measurements.
Step 1: select base probe head
| Order number | Article | Attn. | B/W | Input Voltage | Input Impedance | Rise time | |||
|---|---|---|---|---|---|---|---|---|---|
|
$11,436.00 USD
|
2 m fiber-optic cable
|
FF-0600A | 600MHz 2m FireFly®, SMA Input | 1:1 | >600 MHz | ±1 V | 200 kΩ || 5.1 pF | < 580 ps | |
|
$15,970.00 USD
|
2 m fiber-optic cable
|
FF-1000A | 1GHz 2m FireFly®, SMA Input | 1:1 | >1.0 GHz | ±1 V | 200 kΩ || 5.1 pF | < 350 ps | |
|
2 m fiber-optic cable
|
FF-1500A | 1.5GHz 2m FireFly®, SMA Input | 1:1 | >1.5 GHz | ±1 V | 200 kΩ || 5.1 pF | <250 ps | ||
|
10 m fiber-optic cable
|
FF-1500A-10M | 1.5GHz 10m FireFly®, SMA Input | 1:1 | >1.5 GHz | ±1 V | 200 kΩ || 5.1 pF | <250 ps | ||
Optional accessory: Power Over Fiber adapter.
Allows continuous operation of the FireFly. Compatible with all FireFly probes. More info about its connectivity can be found here: FireFly® POF Adapter
| Order number | Article | |||
|---|---|---|---|---|
|
FF-POF-A01 | Power-Over-Fiber adapter for continuous operation of the optical probe FireFly®. Interchangeable with the FireFly® battery. Additional PS02/03 power supply channel needed | ||
Step 2: Select FireFly® probe tip cable. Essential + not included.
| Order number | Article | Attn. | B/W | Input Voltage | Input Impedance | Rise time | |||
|---|---|---|---|---|---|---|---|---|---|
|
$863.00 USD
|
|
FF-MMCX-1V | FireFly®, probe tip cable, MMCX | 1:1 | >1.5 GHz | ±1 V | 50 Ω * | <250 ps | |
|
$863.00 USD
|
|
FF-MMCX-10V | FireFly®, probe tip cable, MMCX | 10:1 | >1.3 GHz | ±10 V | 2 MΩ || 3.4 pF | <280 ps | |
|
$863.00 USD
|
|
FF-MMCX-25V | FireFly®, probe tip cable, MMCX | 25:1 | >1.3 GHz | ±25 V | 4,9 MΩ || 2.1 pF | <280 ps | |
|
$863.00 USD
|
|
FF-MMCX-50V | FireFly®, probe tip cable, MMCX | 50:1 | >1.3 GHz | ±50 V | 10 MΩ || 2 pF | <280 ps | |
|
$1,093.00 USD
|
|
FF-MMCX-100V | FireFly®, probe tip cable, MMCX | 100:1 | >1.3 GHz | ±100 V | 9.5 MΩ || 2.1 pF | <280 ps | |
|
$1,093.00 USD
|
|
FF-MMCX-250V | FireFly®, probe tip cable, MMCX | 250:1 | >1.3 GHz | ±250 V | 20 MΩ || 2.1 pF | <280 ps | |
|
$1,725.00 USD
|
|
FF-WSQ-500V | FireFly®, probe tip cable, WSQ | 500:1 | >1 GHz | ±500 V | 40 MΩ || 2.8 pF | <300 ps | |
|
$1,725.00 USD
|
|
FF-WSQ-1000V | FireFly®, probe tip cable, WSQ | 1000:1 | >1 GHz | ±1000 V | 40 MΩ || 2.9 pF | <300 ps | |
|
$1,725.00 USD
|
|
FF-WSQ-1500V | FireFly®, probe tip cable, WSQ | 1500:1 | >1 GHz | ±1500 V | 40 MΩ || 2.7 pF | <300 ps | |
|
$1,725.00 USD
|
|
FF-WSQ-2500V | FireFly®, probe tip cable, WSQ | 2500:1 | >1 GHz | ±2500 V | 40 MΩ || 2.5 pF | <300 ps | |
Step 3: Select Power Supply
Not included in the FireFly® probe head's scope of delivery. A power supply is needed in addition to the included battery-power, which only powers the FireFly® probe head.
| Order number | Article | Input Voltage | Output Current (max.) | Noise | Channels | Power | |||
|---|---|---|---|---|---|---|---|---|---|
|
$1,739.00 USD
|
|
889-09V-PS2-L | 2ch Power supply for remote control with USB and LAN interface | 100-240 V AC, 47-63 Hz | 0.5 A DC continuous / channel | 5 mV RMS | 2 | 20 W | |
|
|
889-09V-PS2 | 2ch Power supply for remote control with USB interface | 100-240 V AC, 47-63 Hz | 0.5 A DC continuous / channel | 5 mV RMS | 2 | 20 W | ||
|
$2,127.00 USD
|
|
889-09V-PS3-L | 4ch Power supply for remote control with USB and LAN interface | 100-240 V AC, 47-63 Hz | 0.5 A DC continuous / channel | 5 mV RMS | 4 | 40 W | |
|
$1,573.00 USD
|
|
889-09V-PS3 | 4ch Power supply for remote control with USB interface | 100-240 V AC, 47-63 Hz | 0.5 A DC continuous / channel | 5 mV RMS | 4 | 40 W | |
|
889-09V-AP01 | 1ch Battery pack, >8hrs operation, no remote control | 700 mA DC | 1 | 20 W | ||||
|
889-09V-PS6-L | 8ch Power supply for remote control with USB and LAN interface | 100-240 V AC, 47-63 Hz | 0.5 A DC continuous / channel | 8 mV RMS | 8 | 60 W | ||
|
889-09V-PS6 | 8ch Power supply for remote control with USB interface | 100-240 V AC, 47-63 Hz | 0.5 A DC continuous / channel | 8 mV RMS | 8 | 60 W | ||
|
|
890-520-915 | Probe connection cable 1.6 m | ||||||
Step 4: Optional connectivity accessories
For optimal signal fidelity, we strongly recommend using soldered-in MMCX or 5.08 mm square pin sockets on your DUT as the interface to the FireFly probe tip. However, we understand that such test points aren’t always available. In those situations, our connectivity accessories offer reliable alternatives for connecting the FireFly to your DUT.
| Order number | Article | Typical Use Case | ||
|---|---|---|---|---|
|
$115.00 USD
|
|
018-294-276 | MMCX to 2x SQ, 2.54mm pitch | Adapting from MMCX to 2x 2.54mm pitch (-) (+) square pins for high-frequency voltage measurements, 42V peak, 30 V rms, 60 V DC |
|
$115.00 USD
|
|
018-294-270 | MMCX to 3x SQ, 2.54mm pitch | Adapting from MMCX to 3x 2.54mm pitch (-) (+) (-) square pins for high-frequency voltage measurements, 42V peak, 30 V rms, 60 V DC |
|
$489.00 USD
|
|
FF-SQ-MMCX5 | 5x MMCX Y-lead adapter, MMCX socket to 2x 0.025'' (0.635mm) socket, compatible with square pins with 0.100'' (2.54mm) space, -40°C to +125°C | Probing standard 0.1" pitch square header pins, common in breadboards and general-purpose PCBs |
|
$431.00 USD
|
|
FF-HTSPAD-MMCX3 | 3x MMCX solder-in cable adapter HT, MMCX socket with 50Ω RF micro coax cable to flex solder-in pad, -40°C to +155°C (1x 0Ω, 1x 36Ω, 1x 75Ω) | Soldering directly onto test pads, especially in compact or embedded RF designs |
|
$155.00 USD
|
|
FF-2XR-MMCX | MMCX Y-Lead, MMCX socket to 2x XR Mini-Hook | Connecting to XR Mini-Hooks for versatile grab-on probing of through-hole or pin legs |
|
$150.00 USD
|
|
FF-UFL-MMCX2 | 2x MMCX cable adapter, MMCX socket with 50Ω RF micro coax cable to UF.L plug, -40°C to +125°C | Connecting to compact RF modules or test equipment with UF.L connectors |
|
$138.00 USD
|
|
FF-HTS-MMCX2 | 2x MMCX solder-in cable adapter HT, MMCX socket with 50Ω RF micro coax cable and open end, -40°C to +155°C | Soldering directly into test circuits or custom setups with bare wire connections |
|
$36.00 USD
|
|
972416100 | Micro SMD-Clip (black) | Probing fine-pitch SMD components or IC leads where minimal footprint is essential |
|
$12.00 USD
|
|
P25-2 | Pico Hook™ (red) | General signal probing where red color coding helps distinguish channels or polarity |
|
$12.00 USD
|
|
P25-0 | Pico Hook™ (black) | Same as above, but black—ideal for ground or second-channel signal referencing |
|
$834.00 USD
|
|
FF-WSQ-4MM-2 | 2x FireFly® adapter, square pins (5.08mm) to 2x 4mm safety banana plugs (male) | Connecting FireFly® probes to lab instruments with standard 4mm banana plug inputs |
|
$454.00 USD
|
|
FF-WSQ-SPADE-2 | 2x FireFly® adapter, square pins (5.08mm) to 2x spade (opening width 4mm) | Connecting FireFly® probes to power terminals or screw posts using spade lugs |
|
$431.00 USD
|
|
FF-MMCX-SPADE-3 | 3x FireFly® adapter, MMCX to 2x spade (opening width 4mm) | Connecting MMCX probes to terminal blocks or screw connectors via spade ends |
Step 5: Optional positioning system (FF-2FOOTER-A already included)
| Order number | Article | ||
|---|---|---|---|
|
FF-2FOOTER-A | 2-foot FireFly® probe holder (Bipod) | |
|
$687.70 USD
|
|
FF-3DPOS200A | FireFly® 3D positioner |
|
$463.45 USD
|
|
FF-HAL10KV-A3 | Set of 3x FireFly® 10kV probe holder adapters |
|
FF-HAL10KV-3 | Set of 3x FireFly® 10kV probe holder adapters. Only for discontinued FireFly® body (FF1500). | |
|
FF-3DPOS200 | FireFly® 3D positioner. Only for discontinued FireFly® body (FF1500). | |
|
FF-2FOOTER | Only for discontinued optical oscilloscope probe FireFly® body (without magnet lock, FF-1500)! Optical oscilloscope probe holder 2 Footer (Bipod) FireFly®. Only for discontinued optical oscilloscope probe FireFly® body (FF1500). | |
Step 6: Optional additional accessories
| Order number | Article | ||
|---|---|---|---|
|
$68.00 USD
|
|
D010031 | 50Ω BNC feedthrough for use with 1MΩ oscilloscope inputs, 0.5W |
As seen on one of our trade shows:
PMK products shown in the image above:
- PMK FireFly® optical probe head with a 10X probe tip, a FF-3DPOS200, mounted to our SKID platform.
- PMK High-Speed Differential Probe HSDP, mounted to our universal 3D-Positioner (lower right corner),
- PMK differential probe BumbleBee® (background), mounted to the SKID platform via a dedicated 3D-Positioner, and connected to the DUT via one of our 4mm Test Point Adapters.
High Voltage Optically-Isolated Probe Series FireFly®
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