Part A
ADF4350BCPZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 1202 PCS
- Package
- LFCSP-32
- Series
- Horário - Geradores de relógios, PLLs, Sintetizadores de Frequências
Replacement verdict
Not a drop-in replacement
The ADF4350BCPZ and ADF4355-2BCPZ-RL7 are both wideband fractional-N PLL synthesizers with integrated VCOs, but they differ in frequency range, supply voltage, package footprint, and output configuration. The ADF4355-2BCPZ-RL7 covers a higher output frequency range and operates from a different supply voltage, while the ADF4350BCPZ offers a lower frequency ceiling and a different package and pinout. These differences in electrical and mechanical characteristics mean the two devices are not directly interchangeable without redesign of the surrounding circuitry and board layout.
Different frequency range
Different supply voltage
Different package footprint
Different output configuration
Parts at a glance
Part B
ADF4355-2BCPZ-RL7
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4154 PCS
- Package
- WFQFN-32
- Series
- Horário - Geradores de relógios, PLLs, Sintetizadores de Frequências
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADF4350BCPZ | ADF4355-2BCPZ-RL7 | Why it matters |
|---|---|---|---|
| Frequency Range (Max) | 4.4 GHz | 4.4 GHz | Both cover the same upper frequency, so neither offers extended tuning range at the high end. |
| Frequency Range (Min) | 137.5 MHz | 53.125 MHz | The ADF4355-2 reaches lower frequencies, enabling lower-band applications the ADF4350 cannot cover directly. |
| Normalized Phase Noise Floor | -216 dBc/Hz | -227 dBc/Hz | A lower phase noise floor yields cleaner spectral performance, critical for high-performance RF synthesis. |
| Maximum RF Output Power | 5 dBm | 5 dBm | Similar output power means comparable drive capability into downstream stages. |
| Supply Voltage | 3.0 V to 3.6 V | 3.15 V to 3.45 V | The narrower supply window of the ADF4355-2 may require tighter regulation in the power design. |
| Package / Pin Count | 32-Lead LFCSP | 32-Lead LFCSP | Identical package and pin count simplify board-level replacement and layout reuse. |
| Integrated VCO | Yes | Yes | Both integrate a VCO, reducing external component count and board space. |
| Maximum Operating Temperature | 85 °C | 85 °C | Same temperature ceiling means equivalent thermal margin for industrial environments. |
| Reference Input Frequency (Max) | 250 MHz | 250 MHz | Matching reference input limits allow the same reference clock source to be reused. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADF4350BCPZ | ADF4355-2BCPZ-RL7 |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Part Status | Active | Active |
| Type | Fanout Distribution, Fractional N, Integer N, Clock/Frequency Synthesizer (RF) | Fanout Distribution, Fractional N, Integer N, Clock/Frequency Synthesizer (RF) |
| PLL | Yes | Yes |
| Input | CMOS, TTL | Clock |
| Output | Clock | Clock |
| Number of Circuits | 1 | 1 |
| Ratio - Input: Output | 1:2 | 1:2 |
| Differential - Input: Output | No/No | No/No |
| Frequency - Max | 4.4GHz | 4.4GHz |
| Divider / Multiplier | Yes/Yes | Yes/Yes |
| Voltage - Supply | 3V ~ 3.6V | 3.15V ~ 3.45V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the key differences between the ADF4350BCPZ and ADF4355-2BCPZ-RL7?
The ADF4350BCPZ is a fractional-N/integer-N PLL synthesizer with an integrated VCO covering 137.5 MHz to 4400 MHz, while the ADF4355-2BCPZ-RL7 is a newer fractional-N/integer-N PLL synthesizer with an integrated VCO covering 54 MHz to 4400 MHz and offers lower phase noise and higher PFD frequency capability. The ADF4355-2 also supports a wider operating range and improved spurious performance compared to the ADF4350.
Are the ADF4350BCPZ and ADF4355-2BCPZ-RL7 pin-compatible?
No. The ADF4350BCPZ is supplied in a 32-lead LFCSP package, while the ADF4355-2BCPZ-RL7 is supplied in a 32-lead LFCSP package as well, but the pin functions and register maps differ between the two devices. They are not directly pin-compatible, and the PCB layout and software register configuration must be redesigned when switching between them.
What is the output frequency range of each device?
The ADF4350BCPZ has an integrated VCO output range of 2200 MHz to 4400 MHz with programmable dividers providing output frequencies from 137.5 MHz to 4400 MHz. The ADF4355-2BCPZ-RL7 has an integrated VCO output range of 3400 MHz to 6800 MHz with programmable dividers providing output frequencies from 54 MHz to 4400 MHz.
How do the phase noise specifications compare between the ADF4350BCPZ and ADF4355-2BCPZ-RL7?
The ADF4355-2BCPZ-RL7 offers improved phase noise performance compared to the ADF4350BCPZ. The ADF4355-2 specifies a normalized phase noise floor of approximately -227 dBc/Hz, while the ADF4350 specifies approximately -216 dBc/Hz. This makes the ADF4355-2 better suited for applications requiring lower phase noise.
What are the supply voltage and power consumption differences?
The ADF4350BCPZ operates from a 3.0 V to 3.6 V supply and typically consumes about 100 mA. The ADF4355-2BCPZ-RL7 operates from a 3.0 V to 3.6 V supply as well, with typical current consumption of approximately 110 mA. Both devices require an external loop filter and reference input.
Can the ADF4355-2BCPZ-RL7 be used as a drop-in replacement for the ADF4350BCPZ?
No. Although both are 32-lead LFCSP PLL synthesizers with integrated VCOs, they differ in pin functions, register maps, VCO frequency range, and output divider configuration. A direct drop-in replacement is not possible; the design must be revalidated with the ADF4355-2 datasheet, including loop filter design, register settings, and PCB layout.
What are the typical applications for each device?
The ADF4350BCPZ is commonly used in wireless infrastructure, test equipment, and clock generation where a wideband frequency synthesizer is required. The ADF4355-2BCPZ-RL7 is used in similar applications but is preferred where lower phase noise, wider frequency coverage down to 54 MHz, and improved spurious performance are needed, such as in high-performance RF instrumentation and microwave point-to-point links.