ADI’s HMC700/HMC701/HMC702/HMC703/HMC704 are silicon germanium SiGe bipolar complementary metal oxide semiconductor (BiCMOS) fractional-N Frequency synthesizers. They include a very low noise digital phase frequency detector (PFD) and a precision controlled charge pump. The fractional synthesizer features an advanced delta-sigma modulator design that allows both ultra-fine step sizes and very low spurious products. Spurious outputs are low enough to eliminate the need for costly direct digital synthesis (DDS) references in many applications.

The HMC701/HMC702 both include an 8 GHz 16-bit RF N-divider, a 24-bit delta-sigma modulator, a very low noise digital phase frequency detector (PFD), and a precision controlled charge pump. In addition the synthesizer supports an external step tuned VCO. These fractional synthesizers feature an advanced delta-sigma modulator design that allows ultra-fine frequency step sizes. A general purpose output (GPO) bus supports the use of multiple VCOs. In addition the synthesizer has a number of auxiliary clock generation modes that can be accessed via the GPO.

The HMC703/HMC704 fractional synthesizers are built upon the high performance PLL platform contained in Analog Devices’ latest generation of PLL+VCO products. These platforms have the best phase-noise and spurious performance in the industry, enabling higher order modulation schemes while minimizing blocker effects in high performance radios. In addition, the HMC703 offers frequency sweep and modulation features, external triggering, double-buffering, exact frequency control, phase modulation, and more while maintaining pin compatibility for the main functions with the HMC700. The HMC704 has been designed as a fractional-N frequency synthesizer that consists of a very low noise digital phase detector, VCO divider, reference divider, and a precision controlled charge pump.

The HMC705 is a low noise gallium arsenide (GaAs) heterojunction bipolar transistor (HBT) programmable divider that can be programmed to divide by any number from N = 1 to N = 17 up to 6.5 GHz. Its high frequency operation along with low phase noise floor are very useful in high-performance, fast-settling, synthesizer architectures.