STW81102ATR - 4.65 GHz Multi-Band RF Synthesizer | STMicroelectronics
MPN: STW81102ATR ✓ ActiveSTW81102ATR Overview
An RF frequency synthesizer is a clock-and-timing semiconductor that locks a voltage-controlled oscillator to a stable reference frequency. Its phase-locked loop compares the divided output with the reference signal, then adjusts the oscillator control voltage until phase and frequency align. This architecture allows an RF system to generate a stable programmable output from a shared reference instead of relying on multiple independent oscillators.
The STW81102ATR uses an integer-N frequency-synthesis architecture and incorporates two differential VCOs with automatic center-frequency calibration. According to the supplied STMicroelectronics datasheet indexing, each VCO provides a direct RF output path, while an internal divider supports an additional lower-frequency division function. Automatic center-frequency calibration helps compensate for process, supply, and temperature variation that would otherwise move the oscillator operating point.
The verified distributor and datasheet listings identify the device as operating up to 4.65 GHz with one listed output and approximately 12 mA device current. These figures make it relevant to RF and wireless-infrastructure designs, although the supplied sources do not provide the complete input-frequency ranges, output-power levels, phase-noise curves, reference sensitivity, lock-time limits, supply-voltage range, temperature range, or recommended decoupling network.
Typical use cases include multi-band wireless infrastructure, local-oscillator generation, RF transceiver frequency planning, and other systems requiring programmable RF output with integrated VCOs. The two calibrated differential VCOs are especially useful when a design requires more than one related RF frequency source or a direct output combined with a divided output. Engineers should still verify phase-noise and spur performance against the exact channel and band requirements.
The main design consideration is that this is a high-frequency analog/RF subsystem rather than a general-purpose digital clock generator. PCB traces, supply filtering, reference routing, ground-plane continuity, and exposed-pad thermal management can affect VCO behavior. Decoupling and loop-filter values must be selected from the complete manufacturer datasheet and reference schematic rather than inferred from the distributor summary.
This page consolidates the verified catalog data for the STW81102ATR and adds application context, engineering caveats, and a drop-in comparison with the identified STW81102AT ordering variant. The comparison distinguishes verified facts from parameters that require confirmation from the full manufacturer datasheet before layout or qualification.
Drop-in alternatives for STW81102ATR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
STW81102AT
✅ Drop-In📋 Reference alternative (not in catalog)
STW81102ATR Specifications
| Device Type | Multi-band RF frequency synthesizer |
| Architecture | Integer-N frequency synthesizer |
| Maximum Stated Frequency | 4.65 GHz |
| Integrated VCO Count | 2 differential VCOs |
| VCO Calibration | Automatic center-frequency calibration |
| Listed Output Count | 1 output |
| Device Current | 12 mA |
| Package | 28-pin VFQFPN |
| Mounting Type | Surface mount |
| Ordering Suffix | R |
| Product Type | Clock generator, PLL, and frequency synthesizer |
| Output Architecture | Direct VCO output and internal divider |
STW81102ATR 28-pin vfqfpn Pin Configuration Guide
Pin configuration for STW81102ATR (28-pin vfqfpn package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for STW81102ATR.
Refer to the datasheet for full pin configuration.
Typical Applications
STW81102ATR is suitable for 6 applications: Multi-Band Wireless Infrastructure RF Synthesis, RF Transceiver Local Oscillator Generation, Programmable RF Test and Measurement Equipment, RF Communication Module Frequency Planning, Industrial RF Monitoring and Control, Frequency-Dependent Sensor Readout.
Multi-Band Wireless Infrastructure RF Synthesis
The STW81102ATR is a candidate for multi-band wireless-infrastructure RF synthesis because it combines an integer-N PLL architecture with two differential integrated VCOs and automatic center-frequency calibration. Its verified catalog maximum is 4.65 GHz, allowing it to address RF generation requirements near that range. The synthesizer can lock its VCOs to a shared reference and produce a stable programmable output. In a base-station or wireless gateway design, this can reduce the number of independent RF oscillator paths and centralize frequency planning. Automatic calibration is particularly useful because it helps the VCO return to its intended center frequency after calibration conditions. The supplied data does not include phase-noise, spur, tuning-range, or lock-time curves, so channel-specific requirements must be checked against the complete manufacturer datasheet before design release.
Recommended
RF Transceiver Local Oscillator Generation
The STW81102ATR fits local-oscillator generation in an RF transceiver whose operating plan requires a programmable reference-derived RF source. Its two differential integrated VCOs provide direct-output paths, while the documented internal divider provides a divided frequency option within the same multi-band synthesis architecture. With a maximum listed frequency of 4.65 GHz, the device can serve designs near that upper operating region. Differential VCO topology can support balanced integration into RF signal chains, but the actual output drive, return loss, isolation, and harmonic performance are not stated in the supplied excerpts. Those characteristics must be confirmed from the complete datasheet and evaluated on the final PCB, where supply noise and reference coupling can influence phase noise and unwanted spurs.
Recommended
Programmable RF Test and Measurement Equipment
The STW81102ATR can support programmable RF test and measurement equipment that needs multiple related frequencies derived from one stable reference. The integer-N synthesizer, dual differential VCOs, automatic center-frequency calibration, and listed 4.65 GHz maximum frequency provide a foundation for source selection across several bands. A laboratory instrument can use the direct output for high-frequency stimulus and the internal divider for lower-frequency test tones or clocking-related signals. Because the supplied excerpts do not list phase-noise floors, spur levels, settling time, tuning granularity, or output power, an instrument designer must map these requirements to the full manufacturer data before selecting filter and attenuator components. Board-level reference isolation and supply filtering are especially important when measuring weak or high-dynamic-range signals.
Recommended
RF Communication Module Frequency Planning
The STW81102ATR is applicable to RF communication modules requiring a compact, programmable frequency-generation function. Its integration of two differential VCOs into a 28-pin VFQFPN package can simplify the physical implementation of multi-frequency RF designs compared with a solution using discrete oscillators and frequency dividers. The device is listed at approximately 12 mA current and supports operation up to 4.65 GHz, making its catalog data relevant to compact wireless hardware. Automatic VCO center-frequency calibration may improve consistency across assembly tolerances and operating conditions. However, the supplied sources do not provide the reference-input range, required loop-filter components, output-power level, or temperature limits, so these values must be obtained from the manufacturer datasheet before schematic capture and PCB commitment.
Recommended
Industrial RF Monitoring and Control
The STW81102ATR can be evaluated for industrial RF monitoring systems that synthesize carrier or excitation frequencies from a common reference. The multi-band integer-N architecture and dual differential VCOs give an industrial controller a way to cover several operating frequencies without relying on multiple independent RF sources. Automatic center-frequency calibration supports repeatable operation when the equipment experiences supply or environmental variation. The verified 28-pin VFQFPN format is suitable for surface-mount assembly, and the listed 12 mA current provides a preliminary indication of the device class. Final suitability for industrial equipment still depends on the missing operating-temperature range, supply limits, phase-noise performance, aging behavior, and calibration-time requirements, all of which must be taken from the complete STMicroelectronics documentation rather than inferred from the search excerpts.
Recommended
Frequency-Dependent Sensor Readout
The STW81102ATR may be used in frequency-dependent sensor and industrial readout systems that require an accurate excitation or reference tone. The programmable RF output, available direct and divided paths, and listed 4.65 GHz upper frequency make the synthesizer useful for systems spanning multiple measurement bands. Sharing a stable reference between the synthesizer and measurement electronics can simplify synchronization because generated and measured frequencies remain phase-related. For capacitive, inductive, resonant, or radar-based sensors, the actual sensor bandwidth and required spectral purity govern the choice. The provided data does not identify phase noise, spur suppression, tuning resolution, settling time, or reference jitter limits, so engineers must compare the complete datasheet with the measurement dynamic range. PCB layout should minimize reference coupling and preserve controlled return paths beneath the RF package.
Recommended
Recommended Products Summary
Engineering reference data for STW81102ATR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | STW81102AT |
|---|---|---|
| Brand | STMicroelectronics | STMicroelectronics |
| Package | VFQFPN-28 | VFQFPN-28 - same package |
| Product Type | Multi-band RF frequency synthesizer | Clock & Timing frequency synthesizer |
| Architecture | Integer-N with dual differential integrated VCOs | Broadly consistent functionality; exact architecture details not stated in supplied excerpt |
| Maximum Stated Frequency | 4.65 GHz | Not stated in supplied comparison excerpt |
| Device Current | 12 mA | Not stated in supplied comparison excerpt |
| VCO Calibration | Automatic center-frequency calibration | Exact calibration implementation not stated in supplied comparison excerpt |
| Electrical Characteristics | Reference configuration specified by STW81102ATR datasheet | Source states that electrical characteristics are somewhat different |
| Price at Quantity 1 | Quotation required as of 2026-10-30 | Quotation required as of 2026-10-30 |
| Lifecycle and Availability | Distributor listings present; confirmed stock and lifecycle program not stated | Distributor comparison listing present; confirmed stock not stated |
Key Differentiators
- Integrated dual-VCO multi-band architecture (vs STW81102AT)
- RF-frequency class with divided-output capability (vs STW81102AT)
- Package compatibility with documented configuration qualification (vs STW81102AT)
Design Notes
Treat the VFQFPN-28 package and its exposed-pad region as an RF-sensitive layout area. Place the device close to the intended RF output and reference-routing points, preserve continuous ground-plane connectivity, and avoid routing high-speed or switching signals beneath the package where practical. The supplied excerpts do not provide the manufacturer's reference layout, so board placement, via geometry, and thermal-pad connections must be copied from the full STMicroelectronics application guidance.
Use the manufacturer-specified loop filter, reference components, and decoupling values; none are available in the supplied excerpts. Keep the PLL reference path and VCO supply connections compact, and maintain the recommended ground-return geometry to reduce supply and reference coupling. A calculated power value cannot be provided from the verified 12 mA catalog figure alone because the operating supply voltage and current conditions are not specified.
Do not treat the same package and similar functional description as proof that STW81102AT is an unconditional replacement for STW81102ATR. The supplied comparison explicitly reports somewhat different electrical characteristics. Before substitution, compare supply voltage, current, reference input, tuning ranges, output drive, phase noise, spurs, lock behavior, control registers, and exposed-pad requirements against the full manufacturer documents.
Validate the synthesized RF output on the completed PCB because VCO performance can be affected by reference noise, supply ripple, grounding, and unwanted coupling. Measure phase noise, close-in spurs, carrier output level, and unwanted harmonics at the relevant operating frequencies. The supplied sources do not provide those performance curves, so laboratory characterization or complete datasheet limits are required before assigning an RF performance budget.
Compliance Information
The supplied search and cross-reference excerpts do not state compliance information for STW81102ATR. Confirm RoHS, REACH, AEC-Q100, lead-free, halogen-free, and conflict-mineral status from the current manufacturer documentation for the exact ordering code.
