VSC7112XJW - 8.5 Gbps PCIe 3.0 Redriver | Microchip
料号： VSC7112XJW ✓ 量产中VSC7112XJW 概述
A PCIe redriver is a signal-conditioning semiconductor used between a transmitter and receiver when PCB traces, cables, connectors, or other interconnect structures have degraded the high-speed differential signal. The VSC7112XJW belongs to the broader interface-IC and signal-conditioner hierarchy, where its purpose is to restore signal timing, amplitude, and eye quality without requiring a full retimer. Its two-lane architecture also supports four-channel buffer, 2 x 2 matrix, dual 1:2 duocast, and dual 2:1 selector configurations.
Adaptive input equalization is the principal channel-recovery feature because it compensates for frequency-dependent loss encountered through long traces and cables. Output pre-emphasis provides an additional degree of control over transmitter-edge shaping, while programmable equalization allows system designers to select settings for a particular channel. Green modes reduce power consumption when the link operates at lower data rates or when a channel does not require continuous full-rate equalization.
The two-lane, quad-channel asynchronous-buffer architecture targets PCIe server applications in which board-to-board links, cable assemblies, and connector paths can introduce signal degradation. Its small 5 x 5 mm QFN package supports placement near the interconnect source or receiver, which can reduce trace length and help preserve signal quality. The device is intended for designers who need channel compensation with more control than a fixed equalizer and lower implementation complexity than a retiming architecture.
Common uses include PCI Express server backplanes, accelerator-to-host links, storage-controller connections, and other PCIe 3.0 paths operating at multi-gigabit rates. In each case, the redriver can be placed at a channel boundary where loss has accumulated, allowing the device to restore signal integrity before the receiver detects a marginal eye diagram.
The primary design consideration is channel tuning. Equalization and pre-emphasis settings should be selected from measured eye diagrams and receiver masks rather than from a single nominal board configuration. Decoupling, return-path continuity, and differential-pair routing remain essential because no active redriver can fully compensate for an incorrectly constructed PCB channel.
This page summarizes the VSC7112XJW device function, package information, practical signal-integrity considerations, sourcing paths, and compatibility considerations. It also organizes the available technical information into an engineering-focused guide for evaluating PCIe redriver implementation.
直接替换替代料： VSC7112XJW ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
VSC7112
✅ 直接替换📋 参考替代料（不在目录中）
VSC7112XJW 规格参数
| Product Type | PCI Express 3.0 redriver and signal conditioner |
| Maximum Data Rate | 8.5 Gbps |
| Channel Architecture | Two-lane, quad-channel asynchronous buffer |
| Supported Operating Modes | 4-channel buffer, 2 x 2 matrix, dual 1:2 duocast, and dual 2:1 selector |
| 电源电压 | 2.5 V |
| Input Equalization | Adaptive and programmable |
| Output Equalization | Programmable pre-emphasis |
| Power Management | Green modes for reduced power at lower data rates |
| Signal Protocol | PCI Express 3.0 |
| 封装 | 32-QFN (5 x 5 mm) |
| 安装类型 | Surface mount |
| Number of Circuits | 2 circuits |
| Manufacturer | Microchip Technology |
VSC7112XJW 32-qfn (5 x 5 mm) 引脚配置指南
VSC7112XJW（32-qfn (5 x 5 mm) 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： VSC7112XJW.
请参阅 数据手册 以查看完整引脚配置。
典型应用
VSC7112XJW 适用于 6 应用s: PCIe Server Backplane Compensation, Accelerator-to-Host PCIe Link, PCIe Storage and Add-In Card Links, Long Backplane Trace Recovery, Configurable PCIe Signal Routing, High-Speed Cable Interface.
PCIe Server Backplane Compensation
The VSC7112XJW is well suited to PCI Express server backplanes where connector and board-level losses reduce the usable eye at the receiver. Its support for asynchronous operation up to 8.5 Gbps matches the PCI Express 3.0 application class, while adaptive input equalization can address frequency-dependent attenuation. Placing the redriver near the end of the impaired channel shortens the remaining lossy path and gives the receiver a more usable signal. Configure equalization and pre-emphasis from measured eye data, then verify compliance across voltage, temperature, and the required lane population.
推荐
Accelerator-to-Host PCIe Link
The VSC7112XJW can improve an accelerator-to-host PCIe path when connector transitions and long PCB routes introduce loss before the host receiver. Two independently configurable lanes support a direct point-to-point arrangement, while the alternate matrix, duocast, and selector modes add routing flexibility. The 5 x 5 mm QFN package permits placement near the connector or receiver. Because equalization settings interact with channel length and transmitter characteristics, validate them using measured eye diagrams and compliance masks rather than relying only on nominal configuration values.
推荐
PCIe Storage and Add-In Card Links
For storage controllers, add-in cards, and other PCIe 3.0 expansion paths, the VSC7112XJW provides active compensation for attenuating interconnects. Adaptive equalization is useful when channel loss varies with data rate or active circuitry, and programmable pre-emphasis allows controlled transmitter-edge shaping. The small 32-QFN footprint supports dense server-board layouts, but power and ground distribution must remain low impedance. Confirm the redriver's configuration pins, reference design, and required decoupling against the manufacturer application guidance before releasing production artwork.
推荐
Long Backplane Trace Recovery
The VSC7112XJW is applicable when long backplane traces accumulate enough insertion loss to narrow the receiver eye at high data rates. Its operation up to 8.5 Gbps addresses the signaling range associated with PCI Express 3.0, and its adaptive equalization compensates for channel loss that changes across frequency. Position the device where the eye is becoming marginal rather than at an arbitrary board edge. Evaluate amplitude, jitter, skew, and crossing after tuning so that the redriver improves the complete eye rather than only one measurement.
推荐
Configurable PCIe Signal Routing
The VSC7112XJW can be configured as a four-channel buffer, 2 x 2 matrix, dual 1:2 duocast, or dual 2:1 selector, allowing one device to support several interconnect topologies. This flexibility is valuable in test equipment and multi-board systems where signal routing changes with the operating mode. Green modes can reduce consumption when the link runs below its maximum rate. Ensure the mode-control implementation follows the manufacturer register and pin requirements, and validate transitions between configurations against the timing expectations of the connected receivers.
推荐
High-Speed Cable Interface
A cable between two circuit boards can introduce substantial high-frequency loss even when each board's local routing is clean. The VSC7112XJW can sit at the cable endpoint and use adaptive input equalization plus programmable pre-emphasis to improve the transmitted signal and receiver eye. Its 2.5 V supply and compact 5 x 5 mm QFN package fit space-constrained cable-adapter and server-controller assemblies. Characterize the complete cable assembly, connector, and board transition together because tuning against only one section may not compensate for the combined channel response.
推荐
推荐产品汇总
工程参考数据： VSC7112XJW ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | VSC7112 |
|---|---|---|
| Brand | Microchip Technology | Microchip Technology |
| Package | 32-QFN (5 x 5 mm) | 32-QFN (5 x 5 mm) |
| Product Type | PCI Express 3.0 redriver | PCI Express 3.0 redriver |
| Maximum Data Rate | 8.5 Gbps | 8.5 Gbps |
| Supply Voltage | 2.5 V | 2.5 V |
| Input Equalization | Adaptive and programmable | Adaptive and programmable |
| Output Pre-Emphasis | Programmable | Programmable |
| Supported Configurations | 4-channel buffer, 2 x 2 matrix, dual 1:2 duocast, and dual 2:1 selector | 4-channel buffer, 2 x 2 matrix, dual 1:2 duocast, and dual 2:1 selector |
| Power Management | Green modes | Green modes |
关键差异点
- Configurable channel arrangement （对比 VSC7112)
- Adaptive channel compensation （对比 VSC7112)
- Compact high-speed implementation （对比 VSC7112)
设计说明
Place the VSC7112XJW close to the channel transition that causes the most degradation, commonly a connector, cable endpoint, or far end of a long trace. Configure adaptive equalization and pre-emphasis using measured eye diagrams rather than trace length alone. Validation should cover receiver eye width, differential amplitude, jitter, and compliance masks across the intended data rates and operating conditions.
Maintain continuous reference planes beneath the high-speed differential pairs and minimize layer transitions between the redriver and the impaired channel. Follow the manufacturer layout for input and output matching networks, supply connections, and decoupling. Keep the 2.5 V and ground-return paths short and low impedance because added supply noise or reference discontinuity can reduce the benefit obtained from equalization.
Do not treat the VSC7112XJW as a substitute for correct PCB design. Check the selected buffer, matrix, duocast, or selector mode against the intended lane routing, and verify every configuration pin and register sequence from the manufacturer documentation. A redriver can mask moderate loss, but excessive loss, impedance discontinuities, or an incorrect pin connection may produce a worse eye than an unconditioned link.
Use the power-supply and decoupling arrangement specified in the VSC7112 application guidance. Account for the additional current drawn by the active equalizers and output drivers when sizing the 2.5 V rail. The Green modes can reduce consumption at lower link rates, but the final power budget should reflect the configured lane mode, equalization state, data rate, and temperature.
合规信息
The available manufacturer and distributor information does not state the requested compliance attributes. Confirm RoHS, REACH, automotive qualification, lead-free status, halogen-free status, and conflict-minerals declarations against the current Microchip product documentation before qualification.
