SY89468UHY - 2:20 1.5 GHz LVDS Clock Fanout | Microchip
MPN: SY89468UHY ✓ Hoạt độngSY89468UHY Tóm tắt
A clock fanout buffer is a clock-management IC that distributes one or more source clocks to multiple destinations while preserving signal amplitude, edge timing, and clock polarity. The SY89468UHY belongs to the hierarchy of clock buffers and drivers, clock distribution ICs, timing-control devices, and broader semiconductor components. Its differential multiplexer allows a system to select between two clock inputs before distributing the selected clock across twenty outputs.
The key features include a 2:1 differential input multiplexer, a 1:20 fanout ratio, LVDS-compatible outputs, and a maximum listed operating frequency of 1.5 GHz. The internal three-pin termination architecture allows small-amplitude differential inputs without an external termination resistor network in the signal path. Fail-Safe Input behavior is designed to prevent metastable output conditions when the selected differential input fails to a DC voltage.
Internally, the part combines a selectable differential input stage, clock distribution circuitry, and twenty low-voltage differential outputs. The output stage is specified for rise and fall times below 270 ps, making it appropriate for high-speed clock-distribution networks. The 2.5 V ±5% supply requirement supports integration into compact, high-speed digital systems while the exposed pad provides a thermal path from the device to the PCB.
Typical uses include telecommunications equipment, industrial control systems, data-conversion equipment, high-speed computing, network timing, and instrumentation. A single SY89468UHY can feed twenty clock destinations when one selected differential source is sufficient, while the multiplexer supports source redundancy or clock switching between two domains. Care is required to preserve LVDS signal integrity through controlled-impedance routing and correctly terminated differential clock networks.
For PCB implementation, place the device close to the clock source, use matched routing for each differential pair, provide a continuous ground reference, and connect the exposed pad to the appropriate ground plane. Verify input amplitude, common-mode voltage, output termination, and downstream rise-time requirements before releasing the layout.
This page combines the device function, verified timing and supply characteristics, sourcing guidance, and practical layout considerations to support clock-tree design. It also distinguishes the verified SY89468UHY ordering code from related manufacturer ordering and comparison candidates, helping engineers determine whether a proposed replacement preserves the required footprint and electrical behavior.
Bộ thay thế dễ dàng lắp đặt cho SY89468UHY — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Không có bộ thay thế dễ dàng lắp đặt sẵn có cho sản phẩm này.
Yêu cầu các bộ thay thếSY89468UHY Thông số kỹ thuật
| Device Type | 2:20 LVDS clock fanout buffer with 2:1 differential input multiplexer |
| Tần số xung maksimum | 1.5 GHz |
| Điện áp cung cấp | 2.5 V ±5% |
| Differential Input Multiplexer Ratio | 2:1 |
| Fanout Ratio | 1:20 |
| Số lượng đầu ra | 20 |
| Number of Differential Inputs | 2 |
| Output Logic Standard | LVDS-compatible |
| Minimum Input Signal Amplitude | 100 mV (200 mVPP) |
| Input Coupling | AC-coupled or DC-coupled |
| Output Rise/Fall Time | Less than 270 ps |
| Input Termination | Internal three-pin termination architecture |
| Fail-Safe Input | Yes |
| Khoảng nhiệt độ hoạt động | -40°C to +85°C |
| Hộp | 64-pin TQFP with exposed pad |
| Kiểu lắp đặt | Surface mount |
| Product Line | Micrel Precision Edge |
Hướng dẫn cấu hình chân SY89468UHY 64-pin tqfp with exposed pad
Cấu hình chân cho SY89468UHY (64-pin tqfp with exposed pad gói). Số thứ tự chân, chức năng và sơ đồ kết nối được xác định trong tài liệu thông số kỹ thuật của nhà sản xuất. Tham khảo nó để biết footprint và hướng dẫn hàn chính xác.
Không có dữ liệu chân cụ thể sẵn có cho SY89468UHY.
Tham khảo: tài liệu kỹ thuật cho cấu hình chân đầy đủ.
Ứng dụng tiêu biểu
SY89468UHY phù hợp cho 6 Áp dụngs: Telecommunications Clock Distribution, Industrial Data-Acquisition Systems, Network Interface Clocking, High-Speed Instrumentation, Data-Converter Synchronization, Server and Computing Clock Trees.
Telecommunications Clock Distribution
The SY89468UHY is suitable for telecommunications clock trees that require one selected differential source to feed twenty destinations. Its 2:1 differential multiplexer allows two clock sources to share a common distribution network, while the 1:20 fanout supports line cards, converters, and interface circuits. The 1.5 GHz operating capability and LVDS-compatible outputs below 270 ps edge rates suit high-speed systems, but designers must confirm source jitter, input common-mode limits, receiver thresholds, and channel skew at the intended operating temperature.
Được đề xuất
Industrial Data-Acquisition Systems
The SY89468UHY can distribute a common sampling or conversion clock across multiple channels in an industrial data-acquisition system. Twenty outputs reduce the number of separate fanout stages required near converters, interface logic, and processing devices. The device accepts differential clocks as small as 100 mV, providing margin for source attenuation, while its AC- and DC-coupling support broadens clock-source compatibility. Practical implementation requires matched differential routing, receiver-specific termination, and validation of deterministic skew across every fanout branch.
Được đề xuất
Network Interface Clocking
The SY89468UHY fits network interface designs that need local fanout of a high-speed differential clock to multiple serial or parallel interface blocks. The 2:1 input multiplexer supports selectable sources, while the twenty LVDS-compatible outputs provide one-to-many distribution within a controlled logic domain. Its sub-270 ps guaranteed output edge rate preserves fast transition timing, but usable bandwidth still depends on input amplitude, loss through controlled-impedance traces, downstream receiver thresholds, and the jitter budget of the complete clock path.
Được đề xuất
High-Speed Instrumentation
The SY89468UHY is useful in high-speed instrumentation where a sampling clock must reach several converters, comparators, or timing blocks. Twenty outputs provide substantial fanout without requiring a cascade of smaller buffers, and the internal input termination architecture accommodates low-amplitude differential sources. Small-signal operation supports source flexibility but demands careful attention to common-mode voltage, connector or trace loss, and return-path continuity. Measure eye height, edge rate, and channel-to-channel skew at each receiver rather than relying only on nominal fanout specifications.
Được đề xuất
Data-Converter Synchronization
The SY89468UHY can supply a common conversion or sampling clock to multiple data-converter channels in a synchronized measurement system. The differential input multiplexer allows the board to choose between two clock domains, and the twenty outputs reduce the need to duplicate source drive paths. Because converter timing performance depends on edge rate, jitter, and skew rather than frequency alone, validate the clock source against each converter's acquisition requirements. Maintain short matched routes and a continuous ground reference to minimize edge distortion and coupling.
Được đề xuất
Server and Computing Clock Trees
The SY89468UHY can distribute a selected low-jitter differential clock among multiple logic domains within a server, accelerator, or computing subsystem. Twenty outputs provide broad fanout for local serializers, interfaces, and clock-consuming blocks, while the Fail-Safe Input function helps manage a failed selected source. The device operates from 2.5 V ±5% and supports clocks up to 1.5 GHz, making it appropriate for high-speed logic, but power integrity and thermal design remain essential. Place decoupling near the supply pins and connect the exposed pad to a low-impedance thermal ground structure.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho SY89468UHY — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này |
|---|---|
| Brand | Microchip Technology |
| Package | 64-pin TQFP with exposed pad |
| Device Function | 2:20 LVDS fanout buffer with 2:1 differential input multiplexer |
| Maximum Clock Frequency | 1.5 GHz |
| Supply Voltage | 2.5 V ±5% |
| Number of Outputs | 20 |
| Output Standard | LVDS-compatible |
| Output Rise/Fall Time | Less than 270 ps |
| Minimum Differential Input Amplitude | 100 mV (200 mVPP) |
| Operating Temperature Range | -40°C to +85°C |
Bảo phân biệt quan trọng
- Combines input multiplexing with twenty-way fanout (vsSY89825UHY)
- Accepts low-amplitude differential clock signals (vsSY89467UHY)
- Guarantees very fast LVDS output transitions (vsSY89825UHY)
Ghi chú thiết kế
Route every differential clock pair as a tightly coupled, impedance-controlled pair over a continuous reference plane. Keep the SY89468UHY close to the clock source and place the input, output, and ground-return structures to minimize loop area. Avoid stubs, abrupt width changes, and splits beneath a differential pair because these discontinuities can degrade the sub-270 ps output edge rate even when the nominal operating frequency is acceptable.
Place the required 2.5 V supply and bypass capacitors close to the device's power and ground connections, following the Microchip SY89468U datasheet layout guidance. Keep high-current return paths out of the sensitive clock-routing region, and verify the supply at the pins rather than only at the regulator output. The exposed pad must be connected to the specified thermal and electrical ground structure, with thermal vias placed where they will not disrupt signal routing.
Validate source amplitude, common-mode voltage, receiver thresholds, termination, channel length, and jitter before treating the 1.5 GHz headline frequency as usable system bandwidth. The SY89468UHY accepts signals as small as 100 mV, or 200 mVPP, but small differential inputs require a clean return path and controlled impedance. Measure output eye quality and channel-to-channel skew at the receivers, especially when long cables or connector transitions are present.
Do not treat a related ordering suffix or a nearby family member as an automatic drop-in replacement. SY89468UHY-TR is an ordering form of the same device, while SY89825UHY uses LVPECL outputs and SY89467UHY belongs to a related family. Confirm output voltage standard, pin function, input architecture, fanout ratio, package, and timing behavior before approving any substitute for an existing SY89468UHY layout.
Thông tin tuân thủ
The manufacturer documentation confirms the -40°C to +85°C industrial temperature range and the Precision Edge product classification. Specific RoHS, REACH, AEC-Q100, lead-free, halogen-free, and conflict-minerals declarations require confirmation from the current manufacturer product documentation.
