Abstract

The modern small form factor DFP and DFB package families from Texas Instruments for digital isolators provide up to 56% PCB package footprint area savings over the traditional isolation packages while maintaining the same creepage and clearance distances and high voltage performance.

The DFP and DFB package families, using 0.5mm pin pitch, provide significant board area reduction, especially in the critical dimension (Y) along the isolation barrier. These smaller packages allow system designers to place more isolation channels in the same space or reduce the total system size. Alternatively, thanks to the shorter dimension along the isolation barrier, routing critical signals across the isolation barrier is easier in the layout thanks to the smaller package. The smaller package and Y dimension provides more flexibility in where and how to place the digital isolator with respect to the devices using the signal on both sides of the isolation barrier.

This application note provides a package by package comparison for the common two, three, four and six channel digital isolators in both the 4mm and 8mm creepage and clearance distance packaging classes. Devices using these packages have certification levels of galvanic (functional isolation), basic certified isolation, and reinforced certified isolation. Refer to the data sheet of the specific device for the certification level or levels.