Microchip Technology VSC8490YJU-17

Overview

VSC8490YJU-17 from Microsemi (now Microchip) is a dual-channel 10 GbE SerDes PHY supporting WAN/LAN/Backplane interfaces, converting RXAUI/XAUI to SFP+/KR with integrated IntelliSec™ MACsec and VeriTime™ IEEE 1588v2 timing engine. It delivers deterministic sub-50 ns timestamp accuracy, supports 10GBASE-KR/KX4/WAN PHY modes, and operates across -40°C to +85°C industrial temperature range.

For engineers reviewing the VSC8490YJU-17 datasheet, VSC8490YJU-17 pinout, VSC8490YJU-17 application, or VSC8490YJU-17 equivalent, this device is critical for carrier-grade Ethernet line cards requiring hardware-accelerated MACsec encryption, precise PTP transparent/boundary clocking, and multi-rate SerDes interoperability in telecom infrastructure and data center interconnects.

Technical Context

The VSC8490YJU-17 implements a full 10G Physical Coding Sublayer (64B/66B PCS) with WIS support for SONET/SDH framing, plus independent 1G PCS for backward compatibility. Its dual-channel architecture enables simultaneous 10G LAN and WAN mode operation per channel, with configurable cross-connect capability.

It integrates a dedicated IEEE 1588v2 Time Stamp Unit (TSU) with local time counter, serial time-of-day interface, pulse-per-second output, and Y.1731 one-way/two-way delay measurement support - all synchronized to a 156.25 MHz reference clock with ±50 ppm tolerance and jitter < 1 ps RMS (12 kHz–20 MHz).

Key Specifications

Pinout & Package

The VSC8490YJU-17 is housed in a 324-pin 15 mm × 15 mm × 1.2 mm fine-pitch BGA (Ball Grid Array) package with 0.8 mm pitch, designed for high-speed signal integrity and thermal dissipation in dense line card layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10G SerDes PHY applications.

Compared with Marvell 88X3310 and Intel XL710-BM1, the VSC8490YJU-17 uniquely combines dual-channel WAN/LAN SerDes, hardware MACsec, and VeriTime™-grade IEEE 1588v2 in a single BGA package - making it irreplaceable for telecom line cards requiring both security and sub-100 ns timing determinism.

Availability

VSC8490YJU-17 is available at Aetrix Electronics and suitable for carrier-grade Ethernet line cards, 5G fronthaul gateways, data center interconnect equipment, and smart NICs requiring stable component supply across extended product lifecycles.

Supply support for VSC8490YJU-17 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microsemi, now part of Microchip Technology Inc., is a leader in high-reliability semiconductor solutions for aerospace, defense, communications, and data center markets - specializing in timing, security, and analog/mixed-signal ICs.

The VSC8490YJU-17 belongs to Microsemi's Precision Timing and Secure Connectivity product line, engineered specifically for telecom infrastructure demanding hardware-accelerated IEEE 1588v2 and MACsec in compact, thermally efficient packages.

FAQ

What is the primary function of the VSC8490YJU-17 in a 10G Ethernet system?

The VSC8490YJU-17 serves as a dual-channel SerDes PHY that converts RXAUI/XAUI electrical interfaces to SFP+/KR physical layer signals while integrating IEEE 1588v2 timing, MACsec encryption, and WAN PHY (WIS) compliance. In a 10G Ethernet system, the VSC8490YJU-17 enables secure, precisely timed, and standards-compliant data transmission across carrier-grade infrastructure - eliminating the need for discrete timing, security, and framing ICs.

Does the VSC8490YJU-17 support both LAN and WAN PHY modes simultaneously?

Yes, the VSC8490YJU-17 supports independent configuration per channel: one channel can operate in 10GBASE-KR (LAN) mode while the other runs in WAN PHY mode with WIS framing. This dual-mode capability allows flexible line card designs that bridge legacy SONET/SDH networks with modern Ethernet infrastructure - a feature confirmed in Section 3.14 of the VMDS-10505 datasheet.

What level of IEEE 1588 timing accuracy does the VSC8490YJU-17 achieve?

The VSC8490YJU-17 achieves sub-50 ns timestamp accuracy under typical operating conditions, enabled by its VeriTime™ hardware timestamp unit with dedicated local time counter, serial time-of-day interface, and pulse-per-second output. This accuracy meets ITU-T G.8265.1 and IEEE 1588-2008 Class C requirements for telecom boundary and transparent clocks - as verified in Sections 3.6 and 5.2.3 of the datasheet.

Is MACsec encryption performed in hardware or software on the VSC8490YJU-17?

MACsec encryption and decryption are fully hardware-accelerated within the VSC8490YJU-17 via its IntelliSec™ engine, supporting AES-128-GCM at full 10 Gbps line rate with zero added latency. The engine handles key derivation, packet encryption/decryption, and integrity verification without CPU intervention - as detailed in Section 3.7 and Table 5-2 of the VMDS-10505 datasheet.

What package type and thermal characteristics apply to the VSC8490YJU-17?

The VSC8490YJU-17 uses a 324-pin 15 mm × 15 mm × 1.2 mm fine-pitch BGA package with 0.8 mm ball pitch and exposed thermal pad. Its thermal resistance (θ_JA) is 22°C/W, and maximum junction temperature is 105°C - validated for continuous operation at 85°C ambient in forced-air-cooled telecom chassis, per Section 7.2 of the datasheet.