Broadcom announced the first high speed 4-level Pulse Amplitude Modulation (PAM-4) Physical Layer transceivers (PHYs) supporting transmission rates of 40/50 Gbps serially over multiple physical media, including direct attach cables (DAC) and optical fiber.
Broadcom said its new 28 nanometer (nm) BCM82040 and BCM82004 PHYs support higher data throughput over existing low bandwidth channels by transmitting more bits per symbol. PAM-4 enables the transmission of 40 Gbps at a baud rate of 20Gbaud, resulting in improved signal integrity while re-using existing channels for higher data throughput and enabling the use of lower cost cables and optics. The PAM4-line code in the new PHYs require half the bandwidth of Non-Return-to-Zero (NRZ) line code, resulting in higher throughput and lower total system cost and power consumption.
Key features include:
- Single 40/50GbE PHY drives 40/50G serial over various media
- Supports a variety of DAC reaches from multiple suppliers
- Enables SMF/MMF optics and silicon photonics
- Low-power 28 nm CMOS design
- Small 7x7mm package fits within QSFP+ form factor, cable assembly and optics modules
“Our new PAM-4 PHYs provide the ideal solution for OEMs and data center operators looking for cost and performance optimization,” said Lorenzo Longo, Broadcom Vice President and General Manager, Physical Layer Products.
