Data Sheet

ADL5721

Rev. 0 | Page 13 of 15

EVALUATION BOARD

The ADL5721-EVALZ comes with an ADL5721 chip. It supports

a single 5 V supply for ease of use. For 5 V operation, the 3.3 V

and 1.8 V test loops are for evaluation purposes only. When the

3.3 V and 1.8 V supply is used, remove the R1 and R2 resistors

from the evaluation board. Figure 34 shows a picture of the

ADL5721-EVALZ lab bench setup.

The band switch feature allows the input P1dB and noise figure

to trade off for optimum system performance. For the lower

frequency band (BAND = 0 V), short Pin 1 and Pin 2 of the

P1 connector. For the higher frequency band (BAND = 1.8 V),

open Pin 1 and Pin 2 of the P1 connector to obtain better

system performance.

INITIAL SETUP

To set up the ADL5721-EVALZ, take the following steps:

1.

Power up the ADL5721-EVALZ with a 5 V dc supply. The

supply current of the evaluation board is approximately

88 mA, which is a combination of the VCC1 (1.8 V) and

the VCC2 (3.3 V) currents.

2.

Connect the signal generator to the input of the ADL5721-

EVALZ.

3.

Connect RFOP and RFON to a 180° hybrid that can work

within the 5.9 GHz to 8.5 GHz frequency range.

4.

Connect the difference output of the hybrid to the spectrum

analyzer. Terminate the sum port of the hybrid to 50 Ω.

See Figure 34 for the ADL5721-EVALZ lab bench setup.

RESULTS

Figure 32 and Figure 33 show the expected results when testing

the ADL5721-EVALZ using the Rev. A version of the evaluation

board and its software. Note that future iterations of the software

may produce different results. See the ADL5721 product page

for the most recent software version.

Figure 32 shows the results of the differential output for an input

of 7.2 GHz at −15 dBm with a BAND = 0 V, with Pin 1 and Pin 2

of the P1 connector shorted. The hybrid and board loss were

not deembedded.

20

10

0

–10

–20

–30

–40

–50

–60

–70

–80

7.15

7.17

7.16

7.18 7.19

7.21

7.23

7.20

7.22

7.24 7.25

FREQUENCY (GHz)

2

RESOLUTION BANDWIDTH = 20kHz

VIDEO BANDWIDTH = 20kHz

SWEEP = 301ms (1001pts)

Figure 32. Results of the ADL5721 with an Input of 7.2 GHz at −15 dBm,

BAND = 0 V

Figure 33 shows the results of the differential output for an

input of 8.5 GHz at −15 dBm with a BAND = 1.8 V, with Pin 1

and Pin 2 of the P1 connector open. The hybrid and board loss

were not deembedded.

20

10

0

–10

–20

–30

–40

–50

–60

–70

–80

2

8.45

8.47

8.46

8.48 8.49

8.51

8.53

8.50

8.52

8.54 8.55

FREQUENCY (GHz)

RESOLUTION BANDWIDTH = 20kHz

VIDEO BANDWIDTH = 20kHz

SWEEP = 301ms (1001pts)

Figure 33. Results of the ADL5721 with an Input of 8.5 GHz at −15 dBm,

BAND = 1.8 V

+5V DC

GND

BAND

INPUT

180° HYBRID FOR DIFFERENTIAL

TO SINGLE-ENDED OUTPUT

RF FREQUENCY GENERATOR

RFOP

SPECTRUM

ANALYZER

RFON

Figure 34. ADL5721-EVALZ Lab Bench Setup