Evaluation Board Hardware; Power Supplies; Rf Output; Loop Filter - Analog Devices EV-ADF5356SD1Z User Manual

UG-1087

EVALUATION BOARD HARDWARE

The EV-ADF5356SD1Z requires an
EVAL-SDP-CS1Z (SDP-B is not recommended).
The EV-ADF5356SD1Z schematics are shown in Figure 7,
Figure 8, and Figure 9. The silkscreens for the evaluation board
are shown in Figure 10 and Figure 11.

POWER SUPPLIES

The board is powered by a 6 V power supply connected to the
red and black banana connectors. Connect the red connector to
a 6 V power supply and the black connector to ground.
The power supply circuitry allows the user two or three separate
low dropout (LDO) regulators to feed the
LDO regulators increases the risk of spur contaminated dc feeds).
The charge pump and VCO supply pins are powered from a 5 V
ADM7150 high performance, low noise regulator. The remaining
supplies are powered from a 3.3 V
low noise regulator.
LED1 indicates when the ADF5356
Switch S1 to switch the 6 V power to the board on and off.

RF OUTPUT

The EV-ADF5356SD1Z has one pair of SMA output connectors:
RFOUTA+ and RFOUTA− (differential outputs). Because they
are sensitive to impedance mismatch, connect the RF outputs to
equal load impedances. If using only one port of a differential
pair, terminate the complementary port with an equal load
terminator (in general, a 50 Ω terminator).
The RFOUTB SMA connector is a single-ended RF output that
operates from 6.8 GHz to 13.6 GHz. If only RFOUTB is used,
power off the RFOUTA+ and RFOUTA− connectors. If left on,
terminate both RFOUTA+ and RFOUTA− SMA connectors with
50 Ω terminators.
SDP-S controller board,
ADF5356 (using fewer
ADM7150 high performance,
is powered on. Use
Rev. 0 | Page 4 of 19
EV-ADF5356SD1Z

LOOP FILTER

The loop filter schematic is included in the board schematic in
Figure 7. Figure 3 shows the loop filter component placements.
For lowest noise at 100 kHz offset, use the following components
(that are inserted on the evaluation board) with a 0.9 mA charge
pump current:

C60 = 22 nF, C59 = 0.47 μF, C61 = 10 nF, C73 = 10 pF

R14 = 220 Ω, R17 = 470 Ω
For lowest rms phase noise, use the following components with
a 0.9 mA charge pump current:

C60 = 1.2 nF, C59 = 33 nF, C61 = 390 pF, C73 = 10 pF

R14 = 1 kΩ, R17 = 3.3 kΩ
R17
RCPOUT
C73
Figure 3. Loop Filter Placement

REFERENCE SOURCE

The evaluation board contains a 122.88 MHz differential output
TCXO from Vectron International. If preferred, the user may
supply either a single-ended or differential reference input to the
REFINA/REFINB SMA connectors. When using an external refer-
ence, remove R12 to disconnect the power rail from the TCXO.
To use a single-ended reference, connect a low noise 122.88 MHz
reference source to SMA REFINB, and connect a 50 Ω terminator
to SMA REFINA. Remove Resistor R27 (100 Ω). To use a differ-
ential reference, connect the differential signal to the SMA REFINA
and SMA REFINB connectors. The differential REFINA/REFINB
SMA connectors can operate at up to a 500 MHz input frequency.

DEFAULT CONFIGURATION

All components necessary for local oscillator generation are
inserted on the board. This board is shipped with the
synthesizer with an integrated VCO, a differential 122.88 MHz
reference TCXO, and a 10 kHz loop filter (I
User Guide
R14
RVTUNE
ADF5356
= 0.9 mA).
CP