ADF4157BRUZ - 6 GHz Fractional-N Frequency Synthesizer | Analog Devices
Teilenummer: ADF4157BRUZ ✓ AktivADF4157BRUZ Übersicht
A fractional-N frequency synthesizer, also called a PLL frequency synthesizer, is a phase-locked loop that multiplies a low-frequency reference source to a high-frequency output while allowing fractional division ratios through digital interpolation. The result is a programmable local oscillator with the resolution of a fractional divider but the phase noise and spur performance of a multi-modulus integer-N architecture. Within the clock and timing hierarchy, this part sits between a crystal oscillator and a full RF transceiver front end.
Key features of the ADF4157BRUZ include an RF input bandwidth reaching 6 GHz, a 25-bit fixed fractional modulus, a programmable charge pump current, and a separate VP pin that allows an extended tuning voltage for a higher tuning range on the VCO. The device supports 3.3 V operation with a documented supply current of 29 mA, and it includes a 3-wire serial interface for programming the INT and FRAC divider values, reference divider ratio, charge pump current, and power-down state.
Architecturally, the ADF4157 uses a digital phase frequency detector to compare the divided feedback signal with the reference, with the resulting error driving the charge pump and external loop filter. The Sigma-Delta fractional interpolator distributes the fractional division error over many PFD cycles, which spreads the fractional spurs away from the carrier and improves the close-in phase noise floor. This makes the device suitable for demanding frequency plans where a single high-performance RF PLL would otherwise be required.
Typical applications include cellular and mmWave transceiver local oscillators, microwave and radar frequency generation, test and measurement instrumentation, wireless infrastructure base station synthesis, and satellite communication modems. The TSSOP-16 body, 4.40 mm wide with 0.173 inch lead span, fits standard surface-mount assembly flows.
When designing around this synthesizer, plan the loop filter for the target reference and VCO, keep the VTUNE node short and shielded from digital return currents, and decouple the VP pin separately from VCC. Confirm that the VCO can be pulled across the full tuning range and that the charge pump current setting matches the loop bandwidth target.
This page consolidates the manufacturer part details, verified distributor inventory channels, pin-compatible drop-in alternatives, and practical loop-filter and layout guidance that engineers typically have to assemble from several separate sources.
Drop-in-Alternativen für ADF4157BRUZ – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit ADF4157BRUZ (gleiche Bauform und Footprint) – abweichend in Package, Charge Pump, Maximum RF Input Frequency, Prescaler, Product Type.
ADF4156
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
ADF4154BCP
✅ Drop-InPreis auf Anfrage
Datenblatt ansehen →ADF4153BCP
✅ Drop-InPreis auf Anfrage
Datenblatt ansehen →ADF4159CCPZ
✅ Drop-In ⚠️ Spezifikationen ungeprüftPreis auf Anfrage
Datenblatt ansehen →ADF4113BRU
✅ Drop-InPreis auf Anfrage
Datenblatt ansehen →ADF4106BRU
✅ Drop-InPreis auf Anfrage
Datenblatt ansehen →ADF4157BRUZ Technische Daten
| PLL Type | Frequency Synthesis (Fractional-N) |
| Maximum RF Input Frequency | 6 GHz |
| RF Bandwidth | To 6 GHz |
| Fixed Modulus | 25-bit |
| Frequency Resolution | Sub-hertz at 6 GHz |
| Supply Voltage Range | 2.7 V to 3.3 V |
| Nominal Supply Voltage | 3.3 V |
| Versorgungsstrom | 29 mA |
| Tuning Voltage Supply Pin | Separate VP pin for extended tuning voltage |
| Charge Pump | Programmable |
| Reference Divider | Programmable |
| Fractional Interpolator | Sigma-Delta based |
| Phase Frequency Detector | Low-noise digital PFD |
| Anzahl der Pins | 16 |
| Gehäuse | 16-lead TSSOP (0.173 inch, 4.40 mm width) |
| Betriebstemperaturbereich | -40 C to +85 C |
| Product Status | Production |
| Schnittstelle | 3-wire serial programming (DATA, CLK, LE) |
ADF4157BRUZ Pin-Konfiguration
| Pin 1 | COM — Ground connection for the charge pump circuitry |
| Pin 2 | VTUNE — VCO tuning voltage input from the external loop filter |
| Pin 3 | VCOIN — RF input from the VCO or prescaler output |
| Pin 4 | REFIN — External reference clock input |
| Pin 5 | RSET — Resistor pin for setting the internal current |
| Pin 6 | GND — Ground connection |
| Pin 7 | VCC — Main power supply input (3.3 V) |
| Pin 8 | VP — Power supply for the charge pump and tuning node, allows extended tuning voltage |
| Pin 9 | SD — Power-down input, logic low powers down the device |
| Pin 10 | LE — Latch enable for the serial interface |
| Pin 11 | DATA — Serial data input for programming the registers |
| Pin 12 | CLK — Serial clock input |
| Pin 13 | PFD — Charge pump output to the external loop filter |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | NC — Not connected (per datasheet) |
| Pin 16 | NC — Not connected (per datasheet) |
Typische Anwendungen
ADF4157BRUZ ist geeignet für 6 Anwendungs: Cellular and mmWave Transceiver Local Oscillator, Microwave and Radar Frequency Generation, Test and Measurement Instrumentation, Wireless Infrastructure Base Station Synthesis, Satellite Communication Modems, Industrial and Automotive Test Equipment.
Cellular and mmWave Transceiver Local Oscillator
The ADF4157BRUZ fits the local oscillator block of a cellular or 5G mmWave transceiver because it synthesizes a low-noise LO up to 6 GHz with sub-hertz tuning resolution from a 25-bit fixed modulus. The Sigma-Delta fractional interpolator spreads fractional spurs away from the carrier, which protects the receiver's adjacent-channel rejection, and the programmable charge pump lets the designer retune loop bandwidth as the reference plan changes. Placing it behind the VCO and a single reference keeps the RF chain short, while the separate VP pin allows a higher tuning voltage when a wide-range VCO is used.
Empfohlen
Microwave and Radar Frequency Generation
For radar front ends and microwave test equipment, the ADF4157BRUZ provides a single-chip fractional-N source with 6 GHz RF bandwidth and programmable reference division, which avoids the cost and size of a multi-part integer-N cascade. The documented 29 mA supply current at 3.3 V keeps the thermal footprint small for sealed outdoor units, and the low-noise digital phase frequency detector improves close-in phase noise for Doppler-sensitive waveforms. Its 16-lead TSSOP body simplifies rework on densely populated microwave modules.
Empfohlen
Test and Measurement Instrumentation
In signal generators and spectrum analyzers, the ADF4157BRUZ acts as a fine-tuning local oscillator whose sub-hertz resolution lets a coarse integer-N divider do most of the work, reducing the tuning range the VCO must cover. The programmable reference divider and charge pump allow the same board to be configured for 10 MHz, 20 MHz, or 100 MHz references, which simplifies product variants. The separate VP supply pin also lets the design extend the tuning voltage for an extended-range VCO without raising the main 3.3 V rail.
Empfohlen
Wireless Infrastructure Base Station Synthesis
Base station radios need accurate, stable carrier references across several bands, and the ADF4157BRUZ covers the 6 GHz range used by microwave backhaul and small-cell equipment. Its 25-bit fractional modulus produces fine channel spacing without the coarse quantization steps of an integer-N divider, and the programmable charge pump supports the narrow loop bandwidth needed to suppress reference spurs. The 16-lead TSSOP footprint and 3.3 V single-rail operation fit typical outdoor radio boards that are thermally constrained and powered from -48 V through a downstream converter.
Empfohlen
Satellite Communication Modems
Satellite and VSAT modems require stable, phase-coherent frequency generation to keep the carrier within the narrow transponder channel, and the ADF4157BRUZ delivers 6 GHz bandwidth with sub-hertz resolution from a single 3.3 V supply. The fractional interpolator reduces deterministic spurs that would otherwise appear as adjacent-channel interference, while the programmable reference divider allows one design to lock to different reference hierarchies on the ground and in orbit. Low 29 mA supply current is valuable in power-limited satellite payload budgets.
Empfohlen
Industrial and Automotive Test Equipment
Production test fixtures that measure RF modules often need a bench frequency reference that can be re-tuned across a wide span quickly. The ADF4157BRUZ allows a single reference design to cover 4 GHz to 6 GHz targets through its fractional-N divider, replacing several discrete oscillator boards. Its -40 C to +85 C operating range supports use in unheated factory and field service environments, and the serial DATA, CLK, and LE interface lets the tester script frequency changes over a parallel or SPI-to-serial bridge without reconfiguring hardware.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für ADF4157BRUZ – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | ADF4156 | ADF4154 | ADF4153 | ADF4159 | ADF4113 |
|---|---|---|---|---|---|---|
| Package | 16-lead TSSOP | 16-lead TSSOP - same | 16-lead TSSOP - same | 16-lead TSSOP - same | 16-lead TSSOP - same | 16-lead TSSOP - same |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Maximum RF Bandwidth | 6 GHz | 4 GHz | 4 GHz | 4 GHz | 6 GHz | 13 GHz |
| Fractional Modulus | 25-bit fixed modulus, fractional-N | 25-bit fixed modulus, fractional-N | 25-bit fixed modulus, fractional-N | 25-bit fixed modulus, fractional-N | 25-bit fixed modulus, fractional-N | Integer-N / dual-modulus |
| Frequency Resolution | Sub-hertz at 6 GHz | Sub-hertz at 4 GHz | Sub-hertz at 4 GHz | Sub-hertz at 4 GHz | Sub-hertz at 6 GHz | Coarse integer-N steps |
| Supply Voltage Range | 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 3.3 V | 2.7 V to 3.3 V | 2.7 V to 3.3 V |
| Separate VP Tuning Supply | Yes | Yes | Yes | Yes | Yes | No dedicated extended tuning supply pin |
| Programmable Charge Pump | Yes | Yes | Yes | Yes | Yes | Yes |
| Operating Temperature Range | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| Number of Pins | 16 | 16 | 16 | 16 | 16 | 16 |
Wichtigste Unterscheidungsmerkmale
- Highest RF bandwidth in the 16-lead TSSOP fractional-N family at 6 GHz (vs. ADF4156)
- Sub-hertz tuning resolution at the top of the band (vs. ADF4106)
- Separate VP pin for extended VCO tuning range (vs. ADF4113)
- Low supply current for portable and space-constrained designs (vs. ADF4154)
Designhinweise
Route the VTUNE and PFD nets as a tight, short pair between the synthesizer, the loop filter, and the VCO. The VTUNE node is a high-impedance summing point, so keep it away from the DATA, CLK, and LE switching traces and from the return path of digital return currents. Place the loop filter capacitors and the RSET resistor close to the pins to minimize parasitic inductance that would otherwise shift the loop bandwidth and inject phase noise.
Decouple VCC and VP independently. Put a high-frequency ceramic capacitor at each pin plus a bulk capacitor near the charge pump section, and keep the VP connection to the charge pump short because the charge pump switching current returns through that path. If VP is driven above 3.3 V for an extended tuning range, verify the absolute maximum rating of the VP pin against the highest tuning voltage your VCO requires, including overshoot during lock.
The most common integration errors are programming an INT and FRAC pair that does not match the real reference frequency, and forgetting that the reference divider value changes the effective phase detector rate. Verify the register writes against the reference actually present on the board, then confirm lock by observing the charge pump error voltage settling on VTUNE. Also confirm the RSET resistor value matches the intended internal current, since it sets charge pump and reference path scaling.
A fractional-N synthesizer distributes fractional energy across many PFD cycles, but the reference spur at the PFD rate can still dominate if the loop is too narrow or if the reference is noisy. Keep the reference input clean, avoid routing REFIN next to the digital interface, and set the loop bandwidth with the charge pump current chosen for the reference frequency. Post-layout, re-check the spur performance because the VTUNE coupling from switching nodes can shift the VCO and create sidebands.
Compliance-Informationen
Analog Devices markets the ADF4157 family as RoHS compliant and the device is listed in production status. The ADF4157BRUZ is rated for -40 C to +85 C industrial operation; no automotive-qualified ordering code is indicated for this part, so AEC-Q100 status is not applicable.
