ADL5354

Data Sheet

Rev. A | Page 18 of 24

APPLICATIONS INFORMATION

BASIC CONNECTIONS

The ADL5354 mixer is designed to downconvert radio frequencies

(RF) primarily between 2200 MHz and 2700 MHz to lower inter-

mediate frequencies (IF) between 30 MHz and 450 MHz. Figure 52

depicts the basic connections of the mixer. It is recommended to

ac couple the RF and LO input ports to prevent nonzero dc

voltages from damaging the RF balun or LO input circuit. The

RFIN matching network consists of a series 1.5 pF capacitor and

a shunt 4.3 nH inductor to provide the optimized RF input return

loss for the desired frequency band.

IF PORT

The mixer differential IF interface requires pull-up choke inductors

to bias the open-collector outputs and to set the output match.

The shunting impedance of the choke inductors used to couple

dc current into the IF amplifier should be selected to provide

the desired output return loss.

The real part of the output impedance is approximately 200 Ω,

which matches many commonly used SAW filters without the

need for a transformer. This results in a voltage conversion gain

that is approximately 6 dB higher than the power conversion gain,

as shown in Table 3. When a 50 Ω output impedance is needed,

use a 4:1 impedance transformer, as shown in Figure 52.

BIAS RESISTOR SELECTION

The IF bias resistors (R1 and R4) and LO bias resistors (R2 and R5)

are used to adjust the bias current of the integrated amplifiers at the

IF and LO terminals. It is necessary to have a sufficient amount

of current to bias both the internal IF and LO amplifiers to optimize

dc current vs. optimum IIP3 performance.

MIXER VGS CONTROL DAC

The ADL5354 features three logic control pins, VGS0 (Pin 24),

VGS1 (Pin 25), and VGS2 (Pin 26), that allow programmability for

internal gate-to-source voltages for optimizing mixer performance

over desired frequency bands. The evaluation board defaults

VGS0, VGS1, and VGS2 to ground.