The 530W is a NAV/COM/GPS (WAAS), which is providing your transponder with a position source for ADS-B out. It also feeds the Dynon screen(s) with position data. You'll have a NAV antenna connected to a splitter that feeds the NAV and GS antenna connectors on the back of the 530.
And typically it's not a true splitter that's used - but actually a diplexer.
The difference is that the splitter is literally just a "T" connection that sends half the signal strength each direction, resulting in a lower quality signal for both end devices. A diplexer actually serves as a bandpass filter that captures most of the energy of a particular frequency range and blocks other frequency ranges. Since the localizer and glideslope are on different frequencies but come in on the same antenna, this works well and sends 80%-90% of the signal strength of the desired frequency to the desired output of the diplexer, which is then routed to your device. This gives a higher signal strength and better service.
Diplexers are, of course, more expensive than splitters - you get what you pay for.