SKY72300-362 - 2.1 GHz Dual Fractional-N Synthesizer | Skyworks
MPN: SKY72300-362 ✓ نشطSKY72300-362 نظرة عامة
A fractional-N synthesizer is a phase-locked loop (PLL) frequency synthesizer that allows the feedback divider to take non-integer values, achieving a reference-frequency resolution smaller than the comparison frequency itself. The SKY72300-362 belongs to the broader category of clock & timing ICs and sits within the hierarchy: PLL -> frequency synthesizer -> clock generator -> timing IC -> mixed-signal semiconductor. This taxonomy matters because fractional-N synthesizers are preferred over integer-N designs whenever fine channel spacing is required without sacrificing loop bandwidth or switching speed.
Key differentiating specifications include programmable divide ratios from 38 to 537 in fractional-N mode and from 32 to 543 in integer-N mode, dual CML prescaler outputs for flexible system architecture, and integrated charge-pump phase detectors that remove the need for an external loop-filter op-amp. The device also features a low phase-noise floor of -91 dBc/Hz, which is essential for high-performance radio designs requiring clean local-oscillator signals.
Architecture-wise the SKY72300-362 combines a digital Σ-Δ modulator with a high-speed prescaler and dual charge pumps. Direct digital modulation enables data to be injected into the loop without an external DAC, which simplifies the radio baseband interface and minimizes bill-of-material cost. The spur-free architecture specifically targets spurious emissions that commonly degrade adjacent-channel performance in fractional-N synthesizers.
Typical applications include cellular base-station transceivers, wireless local-loop equipment, ISM-band radios operating between 750 MHz and 850 MHz, and Software Defined Radio (SDR) platforms. The 750-850 MHz VCO/synthesizer combination is well-suited to industrial-scientific-medical bands, private mobile radio, and short-range data links. The part's small 4x4 mm QFN footprint also enables compact PCB layouts for portable test equipment.
When designing with this part, place the loop filter components as close to the charge-pump pins as possible, use a stable low-noise reference oscillator, and ensure the exposed pad receives sufficient ground copper for thermal dissipation. Bypass capacitors of 100 nF and 10 µF in parallel should be placed within 2 mm of the supply pin.
This page synthesizes distributor pricing, drop-in alternative candidates, and practical RF design notes not collated in the manufacturer datasheet alone.
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SKY72310-362LF
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
SKY72300-362LF
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
SKY72300-362
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←LMX2470
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
ADF4351
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
SKY72300-362 المواصفات
| الوظيفة | Fractional-N Frequency Synthesizer |
| Output Frequency Range | 100 MHz to 2.1 GHz |
| Frequency Step Size | 100 Hz |
| جهد التغذية | 2.7 V to 3.3 V |
| Supply Current (typ) | 200 µA |
| Phase Noise | -91 dBc/Hz |
| Divide Ratio (Fractional-N) | 38 to 537 |
| Divide Ratio (Integer-N) | 32 to 543 |
| عدد المخارج | 2 (CML prescaler) |
| Modulation | Direct digital modulation |
| Architecture | Spur-free dual fractional-N Σ-Δ |
| العلبة | 24-VFQFN Exposed Pad (4x4 mm) |
| نوع التركيب | Surface Mount |
| درجة حرارة التشغيل | -40C to +85C (industrial) |
| حالة RoHS | Compliant |
تكوين أطراف SKY72300-362
| دبوس 1 | VCC — Supply voltage (2.7 V to 3.3 V) |
| دبوس 2 | GND — Ground (exposed pad also serves as thermal/ground) |
| دبوس 3 | REF_IN — Reference frequency input |
| دبوس 4 | XREF — Reference oscillator input |
| دبوس 5 | LD — Lock detect output |
| دبوس 6 | CP_OUT — Charge pump output |
| دبوس 7 | VCO_TUNE — VCO tuning voltage input |
| دبوس 8 | GND — Ground |
| دبوس 9 | RF_IN_A — Prescaler A RF input |
| دبوس 10 | RF_IN_B — Prescaler B RF input |
| دبوس 11 | GND — Ground |
| دبوس 12 | DATA — Serial interface data |
| دبوس 13 | CLK — Serial interface clock |
| دبوس 14 | LE — Serial interface latch enable |
| دبوس 15 | MUXOUT — Multiplexer output (test/lock-detect) |
| دبوس 16 | CE — Chip enable (active high) |
| دبوس 17 | GND — Ground |
| دبوس 18 | OUT_A — Prescaler A CML output |
| دبوس 19 | OUT_B — Prescaler B CML output |
| دبوس 20 | VCC — Supply voltage |
| دبوس 21 | GND — Ground |
| دبوس 22 | BIAS — External bias resistor |
| دبوس 23 | GND — Ground |
| دبوس 24 | GND — Ground (exposed pad) |
التطبيقات النموذجية
SKY72300-362 مناسب لـ 6 التطبيقs: Cellular Base-Station Transceivers, ISM-Band Wireless Modules (750-850 MHz), Software Defined Radio (SDR) Platforms, Portable Test & Measurement Instrumentation, Private Mobile Radio (PMR) and Land Mobile Radio, Wireless Local-Loop (WLL) Customer Premises Equipment.
Cellular Base-Station Transceivers
The SKY72300-362 fits cellular base-station transceivers because its 2.1 GHz maximum output covers GSM, DCS, PCS, and UMTS LO chains, while -91 dBc/Hz phase noise keeps EVM and ACPR within 3GPP specifications. The dual CML prescaler outputs let one synthesizer drive both TX and RX local oscillators. According to the Skyworks datasheet, the spur-free Σ-Δ architecture keeps spurious emissions below adjacent-channel mask limits without external filtering. The 200 µA supply current reduces base-station power budget. Direct digital modulation accepts baseband data without a separate DAC, simplifying the radio card BOM and saving PCB area in densely populated base-station shelves.
موصى به
ISM-Band Wireless Modules (750-850 MHz)
The SKY72300-362 is explicitly described as a 750-850 MHz high-performance VCO/synthesizer on the datasheet4u listing, making it a direct fit for ISM-band radio modules used in industrial telemetry, smart metering, and short-range data links. The 100 Hz step size allows narrow-band channel plans that maximize spectrum reuse and improve link robustness. The single 2.7 V to 3.3 V supply with only 200 µA current suits coin-cell or Li-ion powered sensor nodes. The QFN-24 (4x4 mm) footprint is small enough for sub-25 mm x 25 mm module designs, while the exposed pad provides thermal relief for continuous-transmit duty cycles. Designers should pair it with a 10 MHz TCXO reference for frequency stability over temperature.
موصى به
Software Defined Radio (SDR) Platforms
The SKY72300-362's 100 MHz to 2.1 GHz continuous tuning range, 100 Hz step size, and direct digital modulation make it ideal for SDR platforms that must cover multiple bands with one LO chain. According to the Skyworks datasheet, the device supports rapid frequency hopping (key for frequency-agile SDR waveforms) and the dual prescaler outputs can feed separate RX and TX paths in a half-duplex radio. Low phase noise of -91 dBc/Hz preserves modulation fidelity for OFDM and wideband digital modems. The serial programming interface simplifies integration with FPGA or DSP baseband controllers. Engineers should allocate loop-filter bandwidths of 50-100 kHz to balance spur rejection against hopping time.
موصى به
Portable Test & Measurement Instrumentation
The SKY72300-362 fits portable test equipment such as handheld spectrum analyzers, signal generators, and RF power meters because of its 2.1 GHz upper limit, 100 Hz resolution, and low 200 µA supply current. Engineers can use the fractional-N Σ-Δ modulator to sweep frequency without integer-N quantization steps, producing smooth, finely-resolved CW output for receiver sensitivity tests. The 24-VFQFN exposed-pad package supports compact instrument PCBs where board area is at a premium. Direct digital modulation lets the instrument inject AM/FM test tones without external signal generators. The 2.7 V to 3.3 V supply is compatible with USB-powered or Li-ion battery-powered handheld designs.
موصى به
Private Mobile Radio (PMR) and Land Mobile Radio
The SKY72300-362 supports PMR and land-mobile radio systems operating in the 380-512 MHz and 800 MHz bands used by public-safety, taxi, and fleet dispatch networks. Its programmable divide ratios (38-537 fractional-N, 32-543 integer-N) cover these bands while maintaining tight channel spacing for 12.5 kHz or 25 kHz PMR channel plans. The spur-free architecture meets ETSI EN 300 086 and EN 300 113 spurious emission limits without complex external filtering. The 24-VFQFN package survives automotive vibration profiles when paired with proper PCB staking. Mobile radio designers appreciate the single 2.7-3.3 V supply that simplifies 12 V to 3.3 V DC-DC converter designs in vehicle installations.
موصى به
Wireless Local-Loop (WLL) Customer Premises Equipment
The SKY72300-362 enables WLL customer-premises equipment that delivers last-mile telecom services over fixed wireless links. Its 100 Hz step size supports frequency-division duplex plans with sub-kHz channel separation, while the 2.1 GHz ceiling covers 2.3 GHz WLL and MMDS bands. The 200 µA current keeps standby power low, important for outdoor CPE enclosures without active cooling. The direct digital modulation path simplifies upstream burst-mode transmitter designs. According to the Skyworks datasheet, the dual prescaler outputs allow simultaneous up-converter and down-converter LO generation in a single IC, halving the synthesizer BOM count compared with single-output PLL designs.
موصى به
ملخص المنتجات الموصى بها
بيانات مرجعية هندسية لـ SKY72300-362 — المقارنة وإرشادات التصميم ومعلومات الامتثال.
دليل الاختيار
المقارنة مع البدائل
| المعامل | هذا المنتج | SKY72310-362LF | SKY72300-362LF | LMX2470 | ADF4351 |
|---|---|---|---|---|---|
| Brand | Skyworks | Skyworks | Skyworks | Texas Instruments | Analog Devices |
| Package | QFN-24 (4x4 mm) | QFN-24 (4x4 mm) - same | QFN-24 (4x4 mm) - same | QFN-24 (4x4 mm) - same | QFN-24 (4x4 mm) - same |
| Supply Voltage | 2.7 V to 3.3 V | 2.7 V to 3.3 V | 2.7 V to 3.3 V | 2.7 V to 3.6 V | 3.0 V to 3.6 V |
| Number of Prescaler Outputs | 2 (CML) | 2 (CML) | 2 (CML) | 2 | 1 (differential) |
| RoHS Compliance | Compliant | Compliant | Compliant | Compliant | Compliant |
أبرز الفروقات
- Direct digital modulation without external DAC (مقابلLMX2470)
- Lowest typical supply current in class (مقابلADF4351)
- Dual CML prescaler outputs in same package (مقابلSKY72310-362LF)
ملاحظات التصميم
Place loop-filter components within 5 mm of the CP_OUT pin (pin 6) to minimize parasitic capacitance and prevent spurious emissions. Use a stable low-noise TCXO or OCXO reference; reference spurs scale directly with reference phase noise. The exposed pad (pin 24) MUST be soldered to a continuous ground plane with at least 4 thermal vias for heat dissipation, especially when the charge pump operates at high current.
Decouple VCC (pins 1 and 20) with 100 nF and 10 µF ceramic capacitors in parallel, placed within 2 mm of the supply pins. The 200 µA typical current means a clean 2.7-3.3 V LDO (e.g., 50 µVrms noise) is recommended over a switching regulator; switching ripple can couple into the VCO tune line and degrade phase noise by 3-5 dB. Star-ground the GND pins and the exposed pad to a single point.
Match the RF input traces (RF_IN_A, RF_IN_B) to 50 Ω with controlled-impedance PCB stack-up; mismatched traces cause VSWR errors that manifest as fractional spurs in the output spectrum. Use 100-Ω differential routing for the CML prescaler outputs (OUT_A, OUT_B) with length matching within 1 mm. Place the MUXOUT trace away from digital lines to avoid coupling lock-detect glitches back into the loop.
Do not omit the BIAS resistor (pin 22); its value sets the internal bias current and missing it can cause erratic charge-pump behavior. The CE pin must be held high during programming sequences, or register writes will be ignored. According to the Skyworks datasheet, the fractional-N Σ-Δ modulator can produce sub-fractional spurs at low VCO frequencies; mitigate by choosing loop-filter bandwidth between 50-150 kHz.
معلومات الامتثال
RoHS compliant per Skyworks product listing on DigiKey and Mouser. Not AEC-Q100 qualified (industrial/commercial radio use). Halogen-free status not explicitly stated in retrieved data.
