With an on-chip VCO and PLL, the ADF4350 synthesizer from Analog Devices Inc. is the first fully integrated synthesizer to operate over an exceptionally wide continuous frequency range, 137.5 MHz to 4.4 GHz, according to ADI. The company has also introduced a family of highly integrated active and passive mixers that are well-suited for use in diversity communications applications.

Article Tools

• 

The ADF4350 eliminates the need for as many as 10 individual VCO/PLL combinations. The on-board VCO features phase-noise of –137 dBc/Hz at a 1-MHz offset when operating at 2.1 GHz and –155 dBc/Hz at a 1-MHz offset when operating at 137.5 MHz. This corresponds to an integrated rms phase error of 0.36° at 2.1 GHz and 0.02° at 137.5 MHz. The synthesizer provides two RF output ports and enables the user to digitally program the output power level. The device supports both integer-N and fractional-N operating modes, allowing the user to determine the optimal spur and phase-noise performance via software controls for optimal performance and faster time-to-market.

The new mixers include the ADL5802 wideband active device, which provides high linearity and modest gain in the industry’s smallest package footprint, a 4- by 4-mm LFCSP. The family also includes the ADL5356, ADL5358, and ADL5360 band-specific passive mixers, which offer high linearity and a low-noise figure with integrated IF amplifiers. Their gain is higher than other active and competing passive devices.

The ADL5802 dual active mixer achieves a IIP3 of 27 dBm and a single-sideband noise figure of 11 dB with a conversion power gain of 1.5 dB. For high-linearity applications, the ADL5802 dissipates less than 1 W from a 5-V power supply. The device provides high dynamic-range frequency conversion from 300 MHz to 6 GHz.

The ADL5356, ADL5358, and ADL5360 dual passive mixers with integrated IF amplifiers and integrated RF balun achieve an IIP3 of 26 dBm, a single-sideband noise figure of less than 10 dB, and an industry-leading 10-dBm blocker noise figure of 16.5 dB. The passive mixers with IF amplifiers provide a conversion power gain of 8.5 dB to 9.5 dB within a 6- by 6-mm LFCSP footprint. The 5-V (nominal) mixers can also run on a 3.3-V supply voltage for power-conscious applications.

The ADF4350 is sampling now with full production scheduled for December. It costs $7.86 each in 5000-unit quantities. The ADL5802, ADL5356, ADL5358, and ADL5360 are sampling now and will be available in volume production in March 2009. The ADL5802 costs $6.80 in 5000-unit quantities. The ADL5356, ADL5358, and ADL5360 cost $9.48 each in 5000-unit quantities.

• Analog Devices

With an on-chip VCO and PLL, the ADF4350 synthesizer from Analog Devices Inc. is the first fully integrated synthesizer to operate from 137.5 MHz to 4.4 GHz.

Related Articles

1. Synthesizer Covers 700 To 8000 MHz
2. High-Performance Active Mixer Overcomes RF Transmitter Design Challenges
3. Six GaAs MMIC Mixers Cover 19 To 90 GHz