PLC Splitters

PLC Splitters: The Passive Core of Every PON Network

A planar lightwave circuit (PLC) splitter divides one optical input into multiple outputs with a fixed, uniform split ratio — most commonly 1:2, 1:4, 1:8, 1:16, 1:32 and 1:64. Because it is built on a silica waveguide chip rather than by fusing fibres together, it delivers a stable split ratio across a wide wavelength range and a much tighter uniformity between output ports than a fused biconic taper coupler.

Why PLC Instead of Fused Coupler

• Uniformity — typical port-to-port uniformity of 1.0-1.5 dB, against 2-3 dB for fused couplers at high split counts
• Wavelength independence — works from 1260 nm to 1650 nm, so the same part serves 1310, 1490 and 1550 nm channels plus OTDR testing
• Reliability — no fused joints to drift, so the insertion loss is stable over temperature and time
• Compactness — a 1:32 splitter fits in a package smaller than a matchbox

Package Types

• ABS box splitter — the steel-tube splitter mounted in a plastic box with SC/UPC or SC/APC adapters on the face. Used in fibre distribution hubs and customer premises.
• Insert cassette / LGX module — a slide-in module that fits a standard 1U 19" splitter shelf. The workhorse of central office and street cabinet deployments.
• Bare tube splitter — the bare splitter with 250 µm or 900 µm pigtails, for splicing into a closure or tray where space is tight.
• Rack mount splitter — a complete chassis with multiple cassettes and adapters, pre-terminated and tested.
• Mini module — compact steel-tube package with connectors, for FTTH drop boxes and wall-mounted enclosures.

Split Ratio and Optical Budget

The theoretical split loss is 10·log10(n) dB, so a 1:8 splitter loses 9.03 dB and a 1:32 loses 15.05 dB before any excess loss. In practice add the splitter's own excess loss and uniformity, plus connector and splice losses. A typical GPON budget allows a 1:32 split ratio up to about 20 km from the OLT.

Practical guidance: use 1:8 or 1:16 for dense urban FTTH where subscribers are close to the OLT; use 1:32 or 1:64 in rural areas with long feeder spans and lower take rates. Cascading two 1:8 splitters gives 1:64 with better budget control than a single 1:64.

Connector and Polish Options

• SC/APC — 8-degree angled, the standard for FTTH in most markets because the angled endface suppresses back reflection to below -60 dB
• SC/UPC — straight polish, used in data centres and legacy networks
• LC/UPC and LC/APC — for high-density shelves where SC connectors use too much panel space
• FC and ST — available on request for industrial and legacy applications

Testing and Quality

Every splitter we ship is tested for insertion loss on every port, uniformity across the output set, return loss, and with a visual inspection of the endface. Test data is supplied per unit. Standard parts meet Telcordia GR-1209 and GR-1221 requirements and are available with IEC 61300 test reports.

Ordering

Huifiber manufactures PLC splitters from 1:2 to 1:64 in ABS box, cassette, bare tube, mini module and rack mount formats, with SC, LC, FC and ST connectors, UPC or APC polish, and 0.9 mm, 2.0 mm or 3.0 mm pigtail cable. Tell us the split ratio, package type and connector and we will quote the right part.