Product Details
●The ADRF6820 is a highly integrated demodulator and synthesizer ideally suited for next generation communication systems. The feature rich device consists of a high linearity broadband I/Q demodulator, an integrated fractional-N phase-locked loop (PLL), and a low phase noise multicore, voltage controlled oscillator (VCO). The ADRF6820 also integrates a 2:1 RF switch, an on-chip tunable RF balun, a programmable RF attenuator, and two low dropout (LDO) regulators. This highly integrated device fits within a small 6 mm × 6 mm footprint.
●The high isolation 2:1 RF switch and on-chip tunable RF balun enable the ADRF6820 to support two single-ended, 50 Ω terminated RF inputs. A programmable attenuator ensures an optimal differential RF input level to the high linearity demodulator core. The integrated attenuator offers an attenuation range of 0 dB to 15 dB with a step size of 1 dB.
●The ADRF6820 offers two alternatives for generating the differential local oscillator (LO) input signal: externally via a high frequency, low phase noise LO signal or internally via the on-chip fractional-N synthesizer. The integrated synthesizer enables continuous LO coverage from 356.25 MHz to 2850 MHz. The PLL reference input can support a wide frequency range because the divide or multiplication blocks can increase or decrease the reference frequency to the desired value before it is passed to the phase frequency detector (PFD).
●When selected, the output of the internal fractional-N synthesizer is applied to a divide-by-2 quadrature phase splitter. From the external LO path, a 1× LO signal can be applied to the built-in polyphase filter, or a 2× LO signal can be used with the divide-by-2 quadrature phase splitter to generate the quadrature LO inputs to the mixers.
●The ADRF6820 is fabricated using an advanced silicon-germanium BiCMOS process. It is available in a 40-lead, RoHS-compliant, 6 mm × 6 mm LFCSP package with an exposed paddle. Performance is specified over the −40°C to +85°C temperature range.
●Applications
● Cellular W-CDMA/GSM/LTE
● Digital predistortion (DPD) receivers
● Microwave point-to-point radios
●### Features and Benefits
● I/Q demodulator with integrated fractional-N PLL
● RF input frequency range: 695 MHz to 2700 MHz
● Internal LO frequency range: 356.25 MHz to 2850 MHz
● Input P1dB: 14.5 dBm at 1900 MHz RF
● Input IP3: 35 dBm at 1900 MHz RF
● Programmable HD3/IP3 trim
● Single pole, double throw (SPDT) RF input switch
● RF digital step attenuation range: 0 dB to 15 dB
● Integrated RF tunable balun for single-ended 50 Ω input
● Multicore integrated VCO
● Demodulated 1 dB bandwidth: 600 MHz
● Demodulated 3 dB bandwidth: 1400 MHz
● 4 selectable baseband gain and bandwidth modes
● Digital programmable LO phase offset and dc nulling
● Programmable via 3-wire serial port interface (SPI)
● 40-lead, 6 mm × 6 mm LFCSP
