Applications involving power MOSFETs driving in sensitive to transient environments and noise require devices with high isolation capabilities. The best way to achieve total galvanic isolation is by using optical devices. In this article we will talk about of a special device for this task recommended by TME.
For this type of application, we highlight the Ixis FDA217, a double photo-driver with a 3.750 Vrms isolation capacity between input and output.
More information can be found on the TME website at:
https://www.tme.com/Document/54650f853b83566909fddbb43e424df2/FDA217.pdf
The photodiode signal is controlled by a high-efficiency LED with characteristics that allow direct excitation of high-power MOSFETs.
An important feature of this component is the presence of a circuit that discharges the MOSFET gate when the LED excitation current is cut. This feature eliminates the need to use external components for this function.
The FDA217 is offered in 3 different configurations given in the table below:
Among the recommended applications for this component, we can mention:
• MOSFET driver
• Programmable Control
• Process control
• Instrumentation
• Telecommunications
• Solid State Relays
• Isolated Switching
• Floating power supplies
Highlights:
* Dual independent and floating outputs for parallel, series or isolated configuration
• Open circuit voltage of 24.4 V in series configuration
• Short circuit current of 18.2A in parallel configuration
• 5mA control current • Integrated shutdown circuit
• High input to output isolation: 3750Vrms
• Replacement of discrete components
• No EMI/RFI generation
• Surface mount version and tape and reel available
• Flammability rating UL 94 V-0
In the datasheet accessed through the link we can find several performance curves in addition to the electrical characteristics. Among this information, we highlight the curve that gives us the switching time as a function of the load capacitance.
