ADL5380

The ADL5380 is a high performance quadrature I-Q demodulator that covers an RF input frequency range from 400 MHz to 6 GHz. With a NF = 13dB, IP1dB = 12dBm and IIP3 = 31dBm at 2.5GHz, the demodulator offers good dynamic range suitable for the demanding infrastructure direct-conversion requirements. The differential RF inputs provide a well-behaved broad-band input impedance of 50 and should be driven from a 1:1 balun for best performance.

Excellent quadrature accuracy is achieved using on-chip polyphase filters for LO quadrature generation. Over a wide range of local oscillator (LO) levels, excellent demodulation accuracy is achieved with phase and amplitude balances < 0.25 dB and < 0.5o, respectively. The demodulated in-phase (I) and quadrature (Q) differential outputs are fully buffered. The ADL5380 provides a typical voltage conversion gain of 4dB Figure 1. Functional Block Diagram independent of differential load impedances as low as 100 with a drive capability exceeding 2Vpp in to 200 .

The fully balanced design minimizes effects from 2nd order distortion. The leakage from the LO port to the RF port is <- 60dBc. Differential DC-offsets at the I and Q outputs are <10mV. Both of these factors contribute to the excellent IIP2 of >60dBm.

The ADL5380 operates off a 4.75V to 5.25V supply with a typical supply current of 200mA. The ADL5380 is fabricated using Analog Devices' advanced Silicon-Germanium bipolar process and is available in a 24-lead exposed paddle LFCSP package. Performance is specified over a -40 to +85 temperature range.