ADL5725

Data Sheet

Rev. 0 | Page 10 of 12

EVALUATION BOARD

The ADL5725-EVALZ comes with an ADL5725 chip. It supports

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

3.3 V and 1.8 V test loops for evaluation purposes only. When

using a 3.3 V or 1.8 V supply, remove the R1 and R2 resistors

from the evaluation board. Figure 19 shows the ADL5725-

EVALZ evaluation board lab bench setup.

INITIAL SETUP

To set up the ADL5725-EVALZ, take the following steps:

1.

Power up the ADL5725-EVALZ with a 5 V dc supply. The

supply current of the evaluation board is approximately

111 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 ADL5725-

EVALZ.

3.

Connect RFOP and RFON to a 180° hybrid that works

within the 17.7 GHz to 19.7 GHz frequency range.

4.

Connect the difference output of the hybrid to the

spectrum analyzer. The sum port of hybrid must be

terminated to 50 Ω.

See Figure 19 for the ADL5725-EVALZ lab bench setup.

RESULTS

Figure 18 shows the expected results when testing the

ADL5725-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 ADL5725 product page

for the most recent software version.

Figure 18 shows the results of the differential output for an input

of 17.7 GHz at −15 dBm. The hybrid and board loss were not

deembedded.

20

10

0

–10

–20

–30

–40

–50

–60

–70

–80

1

17.65

17.67

17.66

17.68 17.69

17.71

17.73

17.70

17.72

17.74 17.75

FREQUENCY (GHz)

RESOLUTION BANDWIDTH = 20kHz

VIDEO BANDWIDTH = 20kHz

SWEEP = 301ms (1001pts)

Figure 18. Test Results at 17.7 GHz

+5V DC

GND

INPUT

RF FREQUENCY GENERATOR

RFON

RFOP

180° HYBRID FOR DIFFERENTIAL

TO SINGLE ENDED OUTPUT

SPECTRUM

ANALYZER

Figure 19. ADL5725-EVALZ Lab Bench Setup