ASM2464PDX - USB4/TB to PCIe Gen4 x4 NVMe Bridge | ASMedia
料号： ASM2464PDX ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
ASM2464PDX 概述
A bridge controller is a protocol-conversion IC that sits between a host interface and a device interface, translating one bus protocol into another. In the USB4 ecosystem, bridge controllers let legacy protocols such as PCI Express ride inside the USB4/Thunderbolt fabric, where USB4 router-to-router tunnels carry PCIe and USB transactions transparently across the domain. Within the power-management-and-connectivity hierarchy of a host system, the ASM2464PDX functions as the device-side endpoint router of a USB4/Thunderbolt daisy chain.
Key features include in-house designed ASMedia USB4/Thunderbolt PHYs, native PCIe Gen4 x4 downstream connectivity for maximum NVMe throughput, and support for USB4, Thunderbolt 3, and USB 3.x legacy host operation. The PDX variant specifically targets general PCIe devices in addition to NVMe SSDs, making it the ASMedia part of choice for Thunderbolt/USB4 eGPU docks and expansion enclosures.
Technically, the ASM2464PDX integrates the USB4/Thunderbolt Gen3 x2 PHY and the PCI Express Gen4 PHY with VDD, VCCL, and VCCH voltage domains. It is clocked from a local 25 MHz crystal, supports multiple GPIO pins for platform customization, and integrates the protocol routers needed to encapsulate PCIe and USB traffic into USB4 tunneling.
Typical applications include USB4/Thunderbolt NVMe SSD enclosures, Thunderbolt eGPU adapters, PCIe accessory expansion docks, and high-speed developer/debug hardware that exposes general PCIe lanes over a single USB-C cable.
Design consideration: the PDX suffix denotes an improved variant of the ASM2464PD focused on power-delivery stability and reduced thermal throttling under sustained high-bandwidth loads such as eGPU traffic; board designs should still provide solid VCCL power planes and thermal relief for sustained Gen4 x4 transfers.
This page synthesizes distributor availability, the documented PD-vs-PDX differences, competitor context (Intel JHL7440/JHL9480), and practical design notes not found in the manufacturer datasheet.
直接替换替代料： ASM2464PDX ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
ASM2464PD
✅ 直接替换📋 参考替代料（不在目录中）
ASM2464PDX 规格参数
| Product Type | USB4/Thunderbolt to PCIe/NVMe bridge controller |
| Host Interface | USB4 40 Gbps / Thunderbolt / USB 3.x |
| Device Interface | PCI Express Gen4 x4 |
| Supported Devices | NVMe SSD and general PCIe devices |
| PHY Architecture | ASMedia in-house designed USB4/Thunderbolt and PCIe PHYs |
| Power Domains | VDD, VCCL, VCCH |
| Reference Clock | Local 25 MHz crystal |
| GPIO | Multiple GPIO pins for customization |
| 封装 | BGA-273 (FCCSP-273, 10x10 mm) |
| 安装类型 | Surface Mount |
| RoHS 状态 | RoHS Green package |
ASM2464PDX bga-273 (fccsp-273, 10x10 mm) 引脚配置指南
ASM2464PDX（bga-273 (fccsp-273, 10x10 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： ASM2464PDX.
请参阅 数据手册 以查看完整引脚配置。
典型应用
ASM2464PDX 适用于 6 应用s: USB4/Thunderbolt NVMe SSD Enclosures, Thunderbolt / USB4 eGPU Adapters, PCIe Accessory Expansion Docks, High-Speed Developer and Debug Hardware, Thunderbolt Storage Arrays, Portable Docking Monitors and Video Accessories.
USB4/Thunderbolt NVMe SSD Enclosures
The ASM2464PDX tunnels PCIe Gen4 x4 across a 40 Gbps USB4/Thunderbolt link, giving NVMe SSD enclosures enough downstream bandwidth to keep pace with high-end M.2 drives that exceed 3 GB/s sustained throughput. In this topology the ASM2464PDX enumerates as the device-side USB4 router, presents the NVMe controller to the host through a PCIe tunnel, and is clocked from a local 25 MHz crystal for low-jitter SuperSpeed link operation. The PDX variant's improved power-delivery stability reduces thermal throttling during long sequential write bursts, which is the dominant failure mode of PD-based enclosures. Place the ASM2464PDX between the USB-C receptacle retimers and the M.2 socket with solid VCCL plane copper to sustain Gen4 signaling margins.
推荐
Thunderbolt / USB4 eGPU Adapters
The ASM2464PDX is ASMedia's designated part for tunneling general PCIe devices - including GPUs - over USB4/Thunderbolt, a role the enclosure-oriented ASM2464PD was not optimized for. In an eGPU adapter, the ASM2464PDX bridges the Thunderbolt/USB4 host fabric to a PCIe Gen4 x4 slot or M.2-to-x4 riser, letting a single USB-C cable carry graphics traffic alongside USB. Community eGPU projects (e.g., ASM2464PD-EGPU on GitHub) confirm the PDX suffix is the variant intended for GPU-class loads. Its enhanced signal integrity under sustained high-bandwidth transfers reduces link retraining and frame drops when an external GPU draws tens of watts over the same board.
推荐
PCIe Accessory Expansion Docks
Because ASMedia explicitly states the ASM2464PDX can be implemented with various types of general PCIe devices in addition to NVMe SSD, it is well suited to Thunderbolt/USB4 docks carrying capture cards, 10 GbE NICs, or DSP accelerator cards. The device encapsulates PCIe transactions into the USB4 fabric as defined by the USB4 specification, so any PCIe Gen3/Gen4 endpoint behind the bridge appears to the host as a native PCIe device. Multiple GPIO pins support board-level customization such as slot-reset handling and LED status. Designers should budget VDD, VCCL, and VCCH rails per the datasheet power tree and verify PCIe Gen4 equalization across the dock's connector and PCB trace lengths.
推荐
High-Speed Developer and Debug Hardware
The ASM2464PDX enables compact USB4-to-PCIe development platforms: FPGA carrier boards, PCIe interposer testers, and protocol-analysis fixtures that expose general-purpose PCIe lanes over a single USB-C cable to laptops and SFF hosts lacking slots. Its in-house ASMedia USB4/Thunderbolt PHYs remove the need for a discrete retimer in short-reach layouts, and the 25 MHz crystal reference simplifies clocking compared with multi-PLL solutions. For debug hardware, the customizable GPIO pins can drive status LEDs or reset control from firmware. Note that bridge throughput is bounded by the Gen4 x4 downstream port, so designs needing more than four lanes should plan switch expansion behind the ASM2464PDX.
推荐
Thunderbolt Storage Arrays
Multi-drive Thunderbolt storage arrays benefit from the ASM2464PDX's PCIe Gen4 x4 upstream tunnel: a PCIe switch behind the bridge can fan out to several NVMe drives, with the aggregate traffic constrained to the 40 Gbps USB4 link. The PDX variant's improved power-delivery stability is relevant here because array controllers draw steadier, higher current than single-SSD designs, and the reduced thermal throttling helps maintain consistent queue depth under RAID rebuild workloads. Implementation requires VCCL/VCCH planes sized for the switch plus drives, and the 10x10 mm BGA-273 footprint keeps the bridge section compact on dense controller boards. Firmware configuration via the GPIO/EEPROM path manages switch reset sequencing.
推荐
Portable Docking Monitors and Video Accessories
USB4/Thunderbolt display docks that also carry PCIe peripherals (capture, SD card readers over PCIe, NVMe scratch disks) can use the ASM2464PDX as the PCIe-tunnel endpoint alongside DisplayPort tunneled by a separate USB4 path. Because the ASM2464PDX only handles the PCIe/USB data tunnel, it pairs naturally with a USB-C mux and PD controller on the same board. Its RoHS Green BGA-273 package suits thin portable-dock form factors, and the local 25 MHz crystal avoids extra clock trees. Thermal design remains important: sustained PCIe Gen4 traffic in a sealed dock should keep the bridge within the datasheet thermal envelope through copper pours rather than heatsinks.
推荐
推荐产品汇总
工程参考数据： ASM2464PDX ——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 | ASM2464PD | JHL7440 |
|---|---|---|---|
| Brand | ASMedia Technology | ASMedia Technology | Intel |
| Host Interface | USB4 / Thunderbolt 40 Gbps / USB 3.x | USB4 / Thunderbolt 40 Gbps / USB 3.x | Thunderbolt 3 40 Gbps |
| Downstream Interface | PCIe Gen4 x4 | PCIe Gen4 x4 | PCIe Gen3 x4 |
| General PCIe Device Support (eGPU) | Yes (explicit) | Limited (SSD-focused) | Yes (Thunderbolt PCIe tunneling) |
| Drop-in Compatible with ASM2464PDX | - | Yes - same footprint | No - different package/pinout |
关键差异点
- General PCIe device support including eGPU （对比 ASM2464PD)
- PCIe Gen4 x4 downstream vs Gen3 competitors （对比 JHL7440)
- Integration of USB4/Thunderbolt PHYs （对比 JHL7440)
设计说明
The ASM2464PDX operates from three power domains - VDD, VCCL, and VCCH - per the ASMedia product page. USB4 Gen3 x2 and PCIe Gen4 PHYs are current-hungry during link training; provide solid VCCL planes with multiple vias to the BGA-273 ball field and bulk capacitance near each rail entry. Verify power-up sequencing and rail voltage levels against the full ASMedia datasheet, which is distributed under NDA. Estimated: budget at least 20% margin above worst-case bridge power when sizing the USB-C PD input, since the bridge shares the cable power budget with the downstream device.
Sustained PCIe Gen4 x4 tunneling (eGPU or RAID workloads) concentrates heat in the bridge's PHY SerDes. The AliExpress PD-vs-PDX comparison documents that the PD variant thermally throttles under sustained eGPU loads, which motivated the PDX revision - indicating thermal margin, not silicon speed, is the practical limit. Provide continuous copper pours on layers adjacent to the BGA-273 and consider a thermal via array under the package. Validate junction temperature under a 30-minute sustained 32 Gbit/s transfer before release.
Route the USB4/Thunderbolt differential pairs as 85-ohm (per USB-C/TB electrical conventions - verify against the ASMedia layout guide) length-matched pairs with reference-plane continuity, and keep PCIe Gen4 x4 traces within the datasheet max length or add equalization-friendly topologies. The 25 MHz crystal must sit close to the IC with guard ground. Gen4 loss budgets are tight: estimate trace, via, and connector insertion loss against the 16 dB-class Gen4 channel budget and simulate the full channel before fabrication.
Do not assume firmware interchangeability between ASM2464PD and ASM2464PDX despite the identical footprint - the PDX power-stability improvements are delivered with firmware configuration, and ASMedia distributes firmware under NDA. Also confirm the variant supports your end application: community documentation states the PD targets NVMe enclosures while the PDX targets general PCIe devices such as GPUs. Using PD silicon for eGPU designs invites the throttling behavior the PDX was created to fix.
合规信息
RoHS Green package per ASMedia product page; JLCPCB listing also marks ROHS compliant. REACH, halogen-free, and conflict-minerals declarations were not found in retrieved data.
