SKY72310-362LF

Clock Generators, PLLs, Frequency Synthesizers Overview

The SKY72310 is a spur-free, single fractional-N frequency synthesizer from Skyworks Solutions Inc., designed for high-performance radio systems requiring low power and fine resolution. It supports a maximum operating frequency of 2.1 GHz with an ultra-fine step size of 100 Hz or less. The device features a high-speed serial interface up to 100 Mbps and three-wire programming. It includes an on-chip crystal oscillator, programmable division ratios, and a phase detector with adjustable gain. Operating at 3 V, it provides a 5 V output to the loop filter and utilizes a 24-pin QFN package.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Ultra-fine frequency resolution enables narrowband applications and drift compensation
• Fast switching speed achieved through high internal reference frequency and large loop bandwidth
• Direct digital modulation capability eliminates the need for external I/Q DACs and quadrature upconverters
• Configurable delta-sigma modulator allows selection between 10-bit and 18-bit fractionality

Clock Generators, PLLs, Frequency Synthesizers Applications

• General purpose RF systems
• 2.5G and 3G wireless infrastructure
• Broadband wireless access
• Low bit rate wireless telemetry
• L-band receivers and satellite communications

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to ensure correct packaging and lead time specifications. Confirm RoHS compliance status as required by your assembly process. Ensure the procurement channel sources directly from authorized distributors to guarantee component authenticity and traceability. Check for any recent product change notices that might affect pin compatibility or electrical characteristics.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this synthesizer when design requirements demand sub-100 Hz frequency steps and rapid acquisition times below 100 µs. The integrated crystal oscillator reduces bill-of-materials cost by eliminating external TCXOs. Choose the 18-bit mode for superior phase noise performance in sensitive receiver chains, or the 10-bit mode for lower power consumption. Ensure the host microcontroller supports the required three-wire serial interface timing for register configuration.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to Skyworks' family of fractional-N frequency synthesizers, specifically engineered for wireless infrastructure and general-purpose RF applications. It serves as a key building block for transceivers needing precise frequency control without complex external filtering. The device integrates functions typically handled by separate PLL and oscillator components, simplifying PCB layout and reducing overall system complexity for broadband and cellular designs.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Public confirmed substitute part numbers are not available in the provided datasheet. Evaluate alternative Skyworks synthesizers based on matching frequency range, package dimensions, and serial interface compatibility. Verify that any replacement maintains the required phase noise floor and switching speed specifications for the target application.

Clock Generators, PLLs, Frequency Synthesizers FAQ

How does the SKY72310 achieve direct digital modulation?

The device uses its high fractionality and small step size to tune to any frequency within the VCO range. Modulation data is programmed into the Modulation Data Register via the serial interface or dedicated pins, allowing instantaneous frequency offsets without external I/Q DACs.

What is the difference between 10-bit and 18-bit modes?

The 18-bit mode offers finer frequency resolution (step size of Fref_main/262144) and better phase noise performance, while the 10-bit mode provides a coarser step size (Fref_main/1024) with potentially lower power consumption.

Can the SKY72310 operate without an external crystal?

No, the SKY72310 contains an on-chip crystal oscillator circuit but requires an external quartz crystal connected to the XtalIN and XtalOUT pins to generate the reference frequency.