2050 MHz to 3000 MHz Quadrature Modulator with
2500 MHz to 2900 MHz Frac-N PLL and Integrated VCO
Data Sheet
ADRF6704
modulator, PLL, and VCO provides for significant board
savings and reduces the BOM and design complexity.
FEATURES
IQ modulator with integrated fractional-N PLL
Output frequency range: 2050 MHz to 3000 MHz
Internal LO frequency range: 2500 MHz to 2900 MHz
Output P1dB: 12.1 dBm @ 2700 MHz
Output IP3: 27.2 dBm @ 2700 MHz
Noise floor: −158.3 dBm/Hz @ 2700 MHz
Baseband bandwidth: 750 MHz (3 dB)
SPI serial interface for PLL programming
Integrated LDOs and LO buffer
The integrated fractional-N PLL/synthesizer generates a 2× fLO
input to the IQ modulator. The phase detector together with an
external loop filter is used to control the VCO output. The VCO
output is applied to a quadrature divider. To reduce spurious
components, a sigma-delta (Σ-Δ) modulator controls the
programmable PLL divider.
The IQ modulator has wideband differential I and Q inputs,
which support baseband as well as complex IF architectures.
The single-ended modulator output is designed to drive a
50 Ω load impedance and can be disabled.
Power supply: 5 V/226 mA
40-lead 6 mm × 6 mm LFCSP
APPLICATIONS
The ADRF6704 is fabricated using an advanced silicon-
germanium BiCMOS process. It is available in a 40-lead,
exposed-paddle, Pb-free, 6 mm × 6 mm LFCSP package.
Performance is specified from −40°C to +85°C. A lead-free
evaluation board is available.
Cellular communications systems
GSM/EDGE, CDMA2000, W-CDMA, TD-SCDMA, LTE
Broadband wireless access systems
Satellite modems
GENERAL DESCRIPTION
Table 1.
IQ Modulator
3 dB RF Output Range
The ADRF6704 provides a quadrature modulator and
synthesizer solution within a small 6 mm × 6 mm footprint
while requiring minimal external components.
Part No.
Internal LO Range
750 MHz
ADRF6701
400 MHz
1250 MHz
1200 MHz
2400 MHz
1550 MHz
2650 MHz
2050 MHz
3000 MHz
1150 MHz
1550 MHz
2150 MHz
2100 MHz
2600 MHz
2500 MHz
2900 MHz
The ADRF6704 is designed for RF outputs from 2050 MHz to
3000 MHz. The low phase noise VCO and high performance
quadrature modulator make the ADRF6704 suitable for next
generation communication systems requiring high signal
dynamic range and linearity. The integration of the IQ
ADRF6702
ADRF6703
ADRF6704
FUNCTIONAL BLOCK DIAGRAM
VCC7
34
VCC6
29
VCC5
27
VCC4
22
VCC3
17
VCC2
10
VCC1
1
36
LOSEL
ADRF6704
40
LON 37
DECL3
DIVIDER
÷2
BUFFER
BUFFER
9
DECL2
38
LOP
2
DECL1
2:1
FRACTION
REG
INTEGER
REG
MUX
12
13
14
DATA
CLK
LE
MODULUS
SPI
INTERFACE
THIRD-ORDER
FRACTIONAL
18 QP
VCO
CORE
INTERPOLATOR
19
32
33
QN
IN
×2
N COUNTER
21 TO 123
PRESCALER
÷2
÷2
0/90
6
8
REFIN
MUX
÷2
CHARGE PUMP
250µA,
500µA (DEFAULT),
IP
–
+
PHASE
FREQUENCY
DETECTOR
TEMP
SENSOR
÷4
750µA,
1000µA
MUXOUT
NOTES
4
7
11 15 20 21 23 25 28 30 31 35
GND
24
5
3
39
16
26
NC
RSET
CP VTUNE ENOP RFOUT
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN.
Figure 1.
Rev. 0
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rights of third parties that may result from its use. Specifications subject to change without notice. No
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