Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > Interface

PLL synthesizer cuts need for active loop filters

Posted: 23 Jun 2010 ?? ?Print Version ?Bookmark and Share

Keywords:PLL synthesizer? loop filter? voltage-controlled oscillator? VCO?

Analog Devices Inc. has released a PLL synthesizer for a variety of applications, including microwave point-to-point systems, PMR (private mobile radio), VSATs (very small aperture terminals), test and instrumentation equipment and aerospace systems.

The ADF4150HV 4.4GHz fractional-N or integer-N PLL synthesizer features a 30V charge pump. Because the device can be used to directly drive high tuning-voltage external voltage-controlled oscillators (VCOs), it removes the need for active loop filters.

The ADF4150HV allows the use of passive loop filter topologies, which do not tend to degrade phase noise when compared to active loop filters. The device incorporates high performance on-chip frequency dividers, allowing the VCO frequency to be divided by 2, 4, 8 or 16 to allow the user to generate RF output frequencies as low as 31.25MHz. Since the ADF4150HV has a 30V charge pump capability, it allows designers to consider wideband (octave range) VCOs. Hence, with the on-chip dividers provided on the ADF4150HV, a designer can simultaneously realize a synthesizer with multioctave tuning capability as well as low phase noise afforded through the use of an external VCO.

The ADF4150HV is supported by ADIsimPLL Version 3.3 design tool, which features many updates and improvements, such as support for 16 new devices, increased phase noise modeling accuracy and Fractional-N spur level estimation, along with enhancements to the tool's New Design Wizard, Time Simulation Engine and Time Domain Simulator features.

Pricing for the ADF4150HV PLL synthesizer in a 32-LFCSP package is $2.49 each in 10,000 units.

- Ismini Scouras

Article Comments - PLL synthesizer cuts need for active...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top