Part A
ADF4156BCPZ
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 1350 PCS
- Package
- WFQFN-20
- Series
- Clock-Timing - Clock Generators, PLLs, Frequency Synthesizers
Replacement verdict
Not a drop-in replacement
The ADF4156BCPZ and ADF4112BCP are both fractional-N PLL frequency synthesizers, but they differ in maximum operating frequency, package footprint, and supply voltage range, so the ADF4112BCP cannot be used as a direct drop-in substitute for the ADF4156BCPZ without design validation.
Different maximum frequency
Different package footprint
Different supply voltage range
Different phase noise profile
Parts at a glance
Part B
ADF4112BCP
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 6937 PCS
- Package
- WFQFN-20
- Series
- Clock-Timing - Clock Generators, PLLs, Frequency Synthesizers
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADF4156BCPZ | ADF4112BCP | Why it matters |
|---|---|---|---|
| Maximum Operating Frequency | 6 GHz | 3 GHz | Determines the highest RF input frequency the PLL synthesizer can handle; the ADF4156 supports higher-frequency applications. |
| Number of Fractional/Integer Modes | Fractional-N | Integer-N | Fractional-N allows finer frequency resolution and lower phase noise for a given reference, while integer-N is simpler and often lower cost. |
| RF Input Frequency Range | 0.5 GHz to 6 GHz | 0.2 GHz to 3 GHz | Defines the usable band of the synthesizer; the two parts cover different application frequency bands. |
| Supply Voltage Range | 2.7 V to 3.3 V | 2.7 V to 3.3 V | Both operate from the same supply range, so power-rail compatibility is maintained. |
| Package Type | 20-Lead LFCSP | 16-Lead LFCSP | Different package footprints and pin counts affect PCB layout and drop-in substitutability. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Both support industrial temperature ranges, so environmental compatibility is equivalent. |
| Programmable Charge Pump Current | Up to 5 mA | Up to 5 mA | Charge pump current affects loop filter design and lock time; matching values simplify loop redesign. |
| Reference Input Frequency | Up to 250 MHz | Up to 250 MHz | Determines the maximum reference clock the phase detector can accept; identical limits ease substitution. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADF4156BCPZ | ADF4112BCP |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| Type | Fractional N Synthesizer (RF) | Clock/Frequency Synthesizer (RF) |
| PLL | Yes | Yes |
| Input | CMOS, TTL | Clock |
| Output | Clock | Clock |
| Ratio - Input: Output | 2:1 | 2:1 |
| Differential - Input: Output | Yes/No | Yes/No |
| Frequency - Max | 6.2GHz | 3GHz |
| Divider / Multiplier | Yes/Yes | Yes/No |
| Voltage - Supply | 2.7V ~ 3.3V | 2.7V ~ 5.5V |
| Mounting Type | Surface Mount | Surface Mount |
| Number of Circuits | 1 | - |
| Operating Temperature | -40°C ~ 85°C | - |
Frequently asked questions
What are the key differences between the ADF4156BCPZ and the ADF4112BCP?
The ADF4156BCPZ is a fractional-N PLL frequency synthesizer with an integrated VCO, operating up to 6 GHz, while the ADF4112BCP is an integer-N PLL synthesizer without an integrated VCO, operating up to 3 GHz. The ADF4156BCPZ supports fractional-N operation for finer frequency resolution, whereas the ADF4112BCP uses integer-N architecture.
Are the ADF4156BCPZ and ADF4112BCP pin-compatible?
No. The ADF4156BCPZ is supplied in a 20-lead LFCSP package, while the ADF4112BCP is supplied in a 16-lead TSSOP package. The different package types and pin counts mean they are not pin-compatible and cannot be directly interchanged on the same PCB footprint.
What is the maximum operating frequency of each device?
The ADF4156BCPZ supports RF input frequencies up to 6 GHz. The ADF4112BCP supports RF input frequencies up to 3 GHz. The higher frequency capability of the ADF4156BCPZ makes it suitable for higher-band applications.
Do both devices require an external VCO?
No. The ADF4156BCPZ includes an integrated VCO, reducing external component count and board space. The ADF4112BCP does not include an integrated VCO and requires an external VCO to complete the PLL loop.
What are the supply voltage requirements for the ADF4156BCPZ and ADF4112BCP?
Both devices operate from a nominal 3.0 V to 3.6 V supply. Designers should consult the respective manufacturer datasheets for detailed supply voltage ranges and decoupling requirements.
Which device offers finer frequency resolution?
The ADF4156BCPZ offers finer frequency resolution because it uses fractional-N architecture, allowing step sizes smaller than the phase detector frequency. The ADF4112BCP, being integer-N, has frequency resolution limited to the phase detector comparison frequency.
Can the ADF4112BCP be used as a drop-in replacement for the ADF4156BCPZ?
No. The devices differ in package type, pin count, PLL architecture (integer-N vs. fractional-N), integrated VCO presence, and maximum operating frequency. A direct drop-in replacement is not possible without redesigning the PCB and validating the PLL loop and frequency plan.