Semtech 10G PON chipset supports triple-generation 50G OLT modules

Semtech has introduced what it describes as an industry-first chipset for 10G passive optical network (PON) optical line terminal (OLT) applications, combining the GN7153C OLT combo IC with the GN28L46 burst-mode transimpedance amplifier (TIA). Together, these two chips form an integrated solution supporting GPON, XGS-PON, and 50G PON, all within a single SFP-DD optical module.

As network operators worldwide begin scaling toward 50G PON deployments, equipment vendors need to support multiple generations of PON technology at once, including GPON (2.5Gbps), XGS-PON (10Gbps), and the newer 50G PON standard, all within the tight physical constraints of an SFP-DD module. At the same time, 50G OLT systems require densely packed ports, making power consumption within each module a critical design consideration.

The GN7153C and GN28L46 chipset brings a new level of integration, lower power consumption, and design flexibility to optical module manufacturers and broadband equipment vendors building next-generation fiber broadband infrastructure. The GN7153C is a 10G PON OLT combo chip that integrates a dual-rate burst-mode limiting amplifier along with laser bias driver outputs, which control how much current drives the module's laser. It's paired with the GN28L46, a high-sensitivity burst-mode TIA, a component that converts weak optical signals into usable electrical current. Together, they form a tightly integrated solution for XGS-PON applications, compliant with the ITU-T G.9807.1 international standard.

The GN7153C operates at lower supply voltages, delivering up to 400mW in power savings per port; across a fully populated 16-port optical line terminal, that adds up to 6.5W of total system-level power savings.

The GN28L46 also includes an accurate Received Signal Strength Indicator (RSSI), which measures incoming signal strength, working together with a burst-mode sample-and-hold circuit built into the GN7153C to improve measurement accuracy. This combination eliminates the need for a separate, standalone RSSI controller chip, further reducing component count and overall bill-of-materials cost.

Amit Thakar, vice president of signal integrity product marketing at Semtech, said the GN7153C helps module suppliers and system vendors realize the promise of 50G PON infrastructure. He said that by integrating the semiconductor optical amplifier (SOA) driver, on-chip RSSI, and dual transmitter optical subassembly (TOSA) bias driver outputs into a single device, and pairing it with the industry-leading sensitivity of the GN28L46 TIA, Semtech is giving customers the design flexibility and power efficiency needed to build next-generation, triple-generation optical line terminal modules.

The GN7153C and GN28L46 chipset is currently available for sampling, with volume production scheduled for September 2026. Semtech will showcase the chipset at CIOE 2026, taking place September 9-11 in Shenzhen, China, at Booth #11C52.