The ADL5382 is a broadband quadrature I-Q demodulator that covers an RF input frequency range from 700 MHz to 2.7 GHz. With a NF = 14 dB, IP1dB = 14.7 dBm, and IIP3 = 33.5 dBm at 900 MHz, the ADL5382 demodulator offers outstanding dynamic range suitable for the demanding infrastructure direct-conversion requirements. The differential RF inputs provide a well-behaved broadband input impedance of 50 Ω and are best driven from a 1:1 balun for optimum performance.
Excellent demodulation accuracy is achieved with amplitude and phase balances ~0.05 dB and ~0.2°, respectively. The demodulated in-phase (I) and quadrature (Q) differential outputs are fully buffered and provide a voltage conversion gain of ~4 dB. The buffered baseband outputs are capable of driving a 2 V p-p differential signal into 200 Ω.
The fully balanced design minimizes effects from second-order distortion. The leakage from the LO port to the RF port is <−65 dBc. Differential dc offsets at the I and Q outputs are typically <10 mV. Both of these factors contribute to the excellent IIP2 specifications which is >60 dBm.
The ADL5382 operates off a single 4.75 V to 5.25 V supply. The supply current is adjustable with an external resistor from the BIAS pin to ground. The ADL5382 is fabricated using the Analog Devices, Inc., advanced Silicon-Germanium bipolar process and is available in a 24-lead exposed paddle LFCSP. Performance is specified over a -40°C to +85°C temperature range.
