TCXO & VCTCXO for PTP/SyncE Communication Sync & Precision GNSS

Why TCXO/VCTCXO Matters in Communication Sync & Precision GNSS

Communication synchronization and precision GNSS timing chains are only as good as their local reference. TCXO and VCTCXO devices improve frequency accuracy over temperature, reduce phase noise and jitter, and support stable timing when a network or GNSS reference becomes degraded.

Typical roles: PTP/IEEE 1588 boundary clocks, SyncE line cards, GNSSDO receivers, small cells, edge routers, and timing CPE requiring ppm-level stability and clean clock edges.

FCom Fuji Crystal TCXO and VCTCXO family for communication sync and precision GNSS

Key FCom TCXO & VCTCXO Series for Communication Sync & GNSS

FVT-7S-WT – Wide-Temperature, High-Stability TCXO

The FVT-7S-WT series targets timing receivers, small base stations and outdoor industrial nodes that must stay stable through temperature swings. It focuses on:

±0.1–0.2 ppm over extended temperature ranges, with CMOS or clipped-sine outputs.
7.0 × 5.0 mm SMD package for robust, board-level timing.
Extended temperature, suitable for outdoor enclosures and cabinets.
Excellent short-term stability, helping GNSS receivers maintain lock and reduce phase wander between holdover intervals.

FVT-2S – Ultra-Compact TCXO/VCTCXO for Modules & Terminals

FVT-2S is a 2.5 × 2.0 mm TCXO/VCTCXO designed for GNSS modules, IoT terminals, compact wireless devices and space-constrained designs.

Very small footprint, ideal for high-density module or SoM designs.
Ppm-level stability across typical industrial temperature ranges.
VCTCXO options allow fine frequency tuning, enabling calibration or integration into small PLL loops.

FVT-3S – 3.2 × 2.5 mm General-Purpose TCXO/VCTCXO

The FVT-3S series offers a balance of size, stability and cost, making it suitable for GNSS equipment, wireless communication modules, test instruments and industrial control systems.

3.2 × 2.5 mm ceramic package with good manufacturability.
Frequency range covering popular communication references (e.g. 10–52 MHz typical).
Available as TCXO and VCTCXO for fixed or voltage-controlled applications.

FVT-3S-LJ – Low-Jitter Differential TCXO

For designs that require very low jitter and differential signaling (such as LVDS or LVPECL), FVT-3S-LJ provides differential outputs in a 3.2 × 2.5 mm package, targeting high-speed serial links and network processors.

Differential outputs for directly clocking SerDes, FPGAs and high-speed interfaces.
Sub-picosecond RMS jitter-class performance for clean eye diagrams.
Ideal for small cells, edge switches and compact timing modules.

Quick Comparison – TCXO/VCTCXO Series Selection

Use this comparison as a first-pass selector. For detailed specs, frequency options, and electrical interfaces, refer to each product page.

Series	Package	Typical Stability	Frequency Range (typ.)	Output	Typical Use
FVT-7S-WT	7.0 × 5.0 mm SMD	As low as ±0.1–0.2 ppm over wide temp	10–52 MHz common refs	Clipped-sine / CMOS, TCXO & VCTCXO	Outdoor small cells, GNSS timing receivers, industrial cabinets.
FVT-2S	2.5 × 2.0 mm SMD	Low-ppm stability over industrial temp	10–52 MHz common refs	Clipped-sine / CMOS, TCXO & VCTCXO	GNSS/IoT modules, terminals, space-constrained designs.
FVT-3S	3.2 × 2.5 mm SMD	Low-ppm stability over industrial temp	Approx. 10–52 MHz	Clipped-sine / CMOS, TCXO & VCTCXO	Wireless modules, industrial control, test instruments.
FVT-3S-LJ	3.2 × 2.5 mm SMD	Ppm-class stability, ultra-low jitter	High-speed serial reference frequencies	Differential (LVDS/LVPECL) & CMOS	SerDes/FPGA clocks, small cells, edge routers and switches.

Application Fit – Where These TCXO/VCTCXO Devices Are Used

Precision GNSS Timing CPE & GNSSDO Modules

In GNSS timing customer premises equipment (CPE), TCXO/VCTCXO devices reduce time error and help hold lock through temperature variations. A stable local oscillator can also improve performance in short GNSS outages, when used in combination with internal PLL algorithms.

For a deeper design discussion, refer to the application guide: TCXO for Sync, GNSS & Satcom Timing.

Small Cells, Edge Routers and Timing CPE

In small cells and timing CPE, TCXO/VCTCXO devices provide a stable reference for network sync ICs, SyncE and IEEE 1588 engines and jitter cleaners. Devices like FVT-3S-LJ can directly clock high-speed SerDes links, while FVT-7S-WT can serve as the core reference for the timing subsystem in outdoor or cabinet-mounted nodes.

For higher-end holdover and timing-discipline performance, pair this stage with a telecom-grade OCXO reference. See Telecom OCXO for PTP/SyncE & Critical Infrastructure Timing and the OCXO Family for Telecom & Critical Infrastructure.

In GNSS, IF and RF chains, you can further improve blocking and selectivity by adding RF/IF SAW filters. See SAW Filter Family for GNSS, IF & RF Front Ends.

Industrial Wireless and Professional Radio Systems

Industrial wireless and professional radio systems often require better stability than consumer devices but must operate within tight power and cost budgets. FVT-2S and FVT-3S provide a balanced solution:

Compact footprints suitable for dense RF and digital layouts.
Good phase noise and jitter performance for clean modulation.
Stable operation over industrial temperature ranges, supporting long product lifetimes.

Where This Family Fits in the Timing Device Application Pyramid

TCXO/VCTCXO sit in the middle to upper layers of the timing device application pyramid, where nodes require strong stability and relatively low jitter but must still balance power, cost and size. For a conceptual overview, see the article Timing Device Application Pyramid.

FAQ – TCXO & VCTCXO for PTP/SyncE Communication Sync & GNSS

Do I need a VCTCXO or is a fixed TCXO sufficient?

A fixed TCXO is often sufficient if you do not need calibration, remote frequency adjustment or integration into a disciplining loop. Use a VCTCXO when a timing IC, PLL or firmware loop will actively tune the oscillator to align with GNSS, network or system-level references.

Can these TCXO/VCTCXO series be combined with OCXO in higher-end timing architectures?

Yes. In chassis or operator-grade timing nodes, an OCXO often serves as the master reference while TCXO/VCTCXO devices distribute clean clocks at the board level. This approach balances holdover performance with power, footprint and cost.

Which series should I start with?

If your design faces wide temperature swings (outdoor cabinets), start with FVT-7S-WT. If board area is the primary constraint, start with FVT-2S. For general designs, start with FVT-3S. For differential SerDes/FPGA clocks, select FVT-3S-LJ.

Designing a communication sync or precision GNSS node? Combine FCom TCXO and VCTCXO devices with our VCXO, OCXO and SAW filter families to build complete RF and timing chains from antenna to baseband.