Part A
ADF4350BCPZ
ADI公司
- Lifecycle
- Active
- Stock
- 1202 件
- Package
- LFCSP-32
- Series
- 時鐘定時-時鐘發生器、PLL、頻率合成器
Replacement verdict
Compatible functional replacement candidate
The ADF4351BCPZ-RL7 is a functional upgrade candidate for the ADF4350BCPZ, sharing the same LFCSP-32 footprint, 3.0 V to 3.6 V supply range, and 4.4 GHz to 4.4 GHz fractional-N PLL synthesizer architecture, while extending the upper frequency range to 4.4 GHz. Designers should validate the extended frequency operation, slightly higher current consumption, and register-level differences before adopting it as a drop-in substitute.
Package and Pinout
High match
Frequency Range
High match
Supply Current
Validation required
Register Compatibility
Validation required
Parts at a glance
Part B
ADF4351BCPZ-RL7
ADI公司
- Lifecycle
- Active
- Stock
- 4291 件
- Package
- LFCSP-32
- Series
- 時鐘定時-時鐘發生器、PLL、頻率合成器
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADF4351BCPZ-RL7 | ADF4350BCPZ | Why it matters |
|---|---|---|---|
| Frequency Range (VCO) | 2.2 GHz to 4.4 GHz | 2.2 GHz to 4.4 GHz | Both cover the same fundamental VCO octave, so the usable output range after dividers is comparable. |
| Maximum RF Output Frequency | 4.4 GHz | 4.4 GHz | Determines the highest synthesizable frequency; identical here, so upper-band applications are equally supported. |
| Phase Frequency Detector (PFD) Max Frequency | 32 MHz | 32 MHz | Higher PFD rates allow wider loop bandwidths and faster settling; both parts share the same limit. |
| Normalized Phase Noise (PN floor) | -216 dBc/Hz | -216 dBc/Hz | Sets the in-band phase noise performance of the synthesizer; equal values indicate comparable spectral purity. |
| Supply Voltage | 3.0 V to 3.6 V | 3.0 V to 3.6 V | Defines the required power rail; identical ranges mean the same supply design can be reused. |
| Package | 32-Lead LFCSP (5x5 mm) | 32-Lead LFCSP (5x5 mm) | Same footprint and pinout enable drop-in board compatibility between the two parts. |
| Output Power (typical) | -4 dBm to +5 dBm (programmable) | -4 dBm to +5 dBm (programmable) | Programmable output level affects drive capability into mixers or amplifiers; matching ranges simplify substitution. |
| Integrated VCO | Yes | Yes | On-chip VCO reduces external component count and board area; both integrate it, preserving BOM simplicity. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Confirms industrial-grade environmental tolerance; identical ratings mean equivalent application suitability. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADF4350BCPZ | ADF4351BCPZ-RL7 |
|---|---|---|
| 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 | CMOS, TTL |
| Output | Clock | Clock |
| Number of Circuits | 1 | 1 |
| Ratio - Input: Output | 1:2 | 1:2 |
| Differential - Input: Output | No/No | No/Yes |
| Frequency - Max | 4.4GHz | 4.4GHz |
| Divider / Multiplier | Yes/Yes | Yes/Yes |
| Voltage - Supply | 3V ~ 3.6V | 3V ~ 3.6V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What is the primary difference between the ADF4351BCPZ-RL7 and the ADF4350BCPZ?
The ADF4351BCPZ-RL7 is a wideband fractional-N/integer-N PLL synthesizer with an integrated VCO covering 35 MHz to 4400 MHz, while the ADF4350BCPZ covers 137.5 MHz to 4400 MHz. The ADF4351 extends the lower frequency range down to 35 MHz and is supplied in a 32-lead LFCSP in tape-and-reel packaging (RL7), whereas the ADF4350 is also offered in a 32-lead LFCSP but with a different minimum output frequency specification.
Are the ADF4351BCPZ-RL7 and ADF4350BCPZ pin-compatible?
Both devices are housed in a 32-lead LFCSP (5 mm × 5 mm) package with the same pin count and footprint, and Analog Devices documents them as pin-compatible within the ADF435x family. However, designers should confirm the register map and control-bit differences against the respective datasheets before treating them as drop-in replacements.
What is the output frequency range of each device?
The ADF4351BCPZ-RL7 provides a fundamental output range of 35 MHz to 4400 MHz, while the ADF4350BCPZ specifies 137.5 MHz to 4400 MHz. Both devices use an integrated VCO with programmable dividers to extend the usable range, but the ADF4351 supports operation at lower frequencies without external components.
Do both parts support fractional-N and integer-N operation?
Yes. Both the ADF4351BCPZ-RL7 and the ADF4350BCPZ are fractional-N/integer-N PLL synthesizers with a programmable modulus, allowing both fractional and integer modes of operation. The fractional-N capability enables finer frequency resolution than integer-N alone.
What are the supply voltage and power consumption specifications?
Both devices operate from a nominal 3.0 V to 3.6 V analog and digital supply, with a charge pump supply of up to 5.5 V. Typical current consumption for the ADF4351 is approximately 75 mA at 3.3 V in fractional-N mode, and the ADF4350 has comparable consumption; exact values should be taken from the respective Analog Devices datasheets for the specific operating mode.
Can the ADF4351BCPZ-RL7 replace the ADF4350BCPZ in an existing design?
Because both are 32-lead LFCSP devices in the same ADF435x family, the ADF4351BCPZ-RL7 can often serve as a replacement for the ADF4350BCPZ, but the design must be revalidated. Differences in the lower frequency limit, register settings, and phase noise performance mean the firmware and loop filter should be checked against the ADF4351 datasheet before substitution.
What is the significance of the RL7 suffix on the ADF4351BCPZ-RL7?
The RL7 suffix indicates tape-and-reel packaging in a 7-inch reel, which is the standard format for automated SMT assembly. The ADF4350BCPZ is supplied in tray or tube packaging depending on the ordering code, so the packaging format differs even though the package body is the same 32-lead LFCSP.
Which device offers better phase noise performance?
According to Analog Devices datasheets, the ADF4351 specifies a normalized phase noise floor of approximately −220 dBc/Hz in fractional-N mode, while the ADF4350 specifies approximately −216 dBc/Hz. The ADF4351 therefore offers a modest improvement in phase noise, but actual performance depends on loop filter design, reference source, and operating frequency.