The Renesas 8V9705x RF Synthesizer functional description consists in a few key operating blocks such as: An input section accepting frequencies up to 310 MHz accommodating popular high frequencies such as 307.2 MHz. A PFD frequency up to 310 MHz may allow for more frequent updates of the integrated VCO thus optimizing the overall phase noise performance. A fractional feedback divider with up to 16 bits of fractional resolution offers an output frequency resolution 16x higher than similar solution available on the market. A wideband VCO with large frequency tuning range that allows for an output frequency coverage from 34.375 MHz to 4400 MHz continuously and two open drain output drivers that provide up to +7 dBm of RF output power. The family of devices also allows for a pin compatible and sometimes software compatible solution to major similar devices from other manufacturers, while allowing the best combination of phase noise, spurious performance, frequency range and power consumption. The low power dissipation along with the support of up to +105°C case temperature simplify the power dissipation challenges in applications without any air flow, for example in some of the wireless base stations radio cards. In addition, the phase noise performance remains very stable and consistent with temperature, so that the user can have a more predictable performance when the temperature varies during operation. The L versions of the devices offer on-chip enhanced low dropout regulators (LDOs) that reduce the complexity of the power supply, relax the performance required for the external LDO, and even in some cases eliminate the need for an external LDO and limit the power supply scheme to a reasonably good DC-DC switching regulator. However, when possible, the use of an external LDO is recommended. Finally, in order to facilitate the debugging phase during the design, the devices offer a Readback mode in order to read the registers. The 8V97051 offers a consistent performance across the whole frequency range of the VCO, while the 8V97053 (or its L version) have been optimized for certain frequency ranges such as for GSM frequencies or around the UTRA band 42 (3.4 GHz to 3.6 GHz).