EVAL-ADF4602EB1Z
Preliminary Technical Data
Rev. PrC | Page 8 of 37
HARDWARE DESCRIPTION
POWER SUPPLIES
The board operates off a single 9V supply which should be
connected at J13. LDO regulators then provide the various
voltages required for each component on the evaluation board.:
a.
+1.8V VINT supply for ADF4602
b.
+3.3V supply for ADF4602
c.
Op5V supply for ADF4602 (Jumper LK1 sets
which of 5V or 3.3V is connected to ADF4602 VBAT.
The default setting is position B, +3.3V)
d.
+3.3V supply to on-board input/output buffers
e.
+5.35V supply to Tx gain stages ADL5542 and
ADL5320
The ADL5320 is supplied from an adjustable regulator. The
supply is set to 5.35V for best ACLR performance from the
device. The ADL5542 is powered from the same regulator for
convenience.
RF FRONT END SECTION
Figure 11 shows the architecture of the RF front end section of
the EVAL-ADF4602EB1Z evaluation board. It is designed to
allow a local class BS operating in band 1, with monitoring of
WCDM/GSM signals in bands 850,900,1800,1900 and
WCDMA band 1.
The board is layed out with the option of a metal can for
shielding the RF section from interference from external
sources, and to prevent unwanted transmissions.
Transmit
On the transmit side, the ADF4602 PA output is amplified by
the ADL5542 and ADL5320 gain stages. The CP0603LGA
coupler couples power back to the ADF4602 power detector
input, and is followed by an isolator and duplexer. An SP6T
(single pole 6 throw) switch selects which of the transmit or
receive monitoring chains is connected to the single antenna.
The signal chain gives +13dBm output power at the antenna
output, while still meeting transmit ACLR specifications as
defined in 3GPP standard TS25.104. Figure 12 shows a typical
ACLR measurement of -47.8dB with +13dBm output power
using test model 5, 8channels. The corresponding EVM is ≈4%.
The ADF4602 output power can be adjusted in software.
Receive
The receive side consists of the necessary saw filters and SPDT
switches for monitoring and receive. The receive matching
consists of a simple series and shunt inductor for each receive
port. Table 2 shows the recommended matching for different
bands.
The evaluation board is populated by default as follows: HB1
matched to 1950MHz, HB2 to 2140MHz and LB to 880MHz.
3GPP
Band
Rx
port
Freq(MHz) Series
L(nH)
Shunt
L(nH)
1
HB1 2140
1.1
1.7
2
HB2 1950
1.9
1.8
3/9
HB2 1830
3
1.7
5/6
LB 880
11
5.6
8
LB 940
9.1
5.1
Table 2. Matching components for receive bands
Figure 11 RF front end section
