SP5669 Datasheet, PDF (9/15 Pages) Mitel Networks Corporation – 2.7GHz I2C Bus Controlled Synthesiser

Double Conversion Tuner Systems
The high 2.7GHz maximum operating frequency and
excellent noise characteristics of the SP5669 enables
the construction of double conversion high IF tuners.
A typical system shown in Fig.8 will use the SP5669 as
the first LO control for full band upconversion to an IF of
greater than 1GHz.
SP5669
The wide range of reference division ratios allows
the SP5669 to be used both for the up converter LO with
a high phase comparator frequency (hence low phase
noise) and the down converter which utilises the device
in a lower comparison frequency mode (which offers a
fine step size).
50–900MHz
First LO
1.6GHz
1650–2700MHz
Reference Clock
SSPP55666599
Second LO
38.9MHz
S^SP^P5⁵6⁶6⁵9⁹
Figure. 8 Example of double conversion from VHF/UHF frequencies to TV IF
4MHz 18pF
Optional application utilising
on–board crystal controlled
oscillator
CONTROL
MICRO
15nF
+30V
68pF _22k
13k3
BCW31
REF ¹⁰ⁿ
ADDRESS
SDA
SCL
P3
P2
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
1n
1n
ADC
P0
P1
+5V
16k
47k
2n2
+12V
OSCILLATOR
OUTPUT
10n
TUNER
Figure. 9 Typical appliction
Application Notes
A generic set of application notes AN168 for designing
with synthesisers such as the SP5659 has been written.
This covers aspects such as loop filter design and
decoupling. This application note is also featured in the
Media Data Book, or refer to the Mitel Semicondor
Internet Site http://www.gpsemi.com.
A generic test/demo board has been produced which
can be used for the SP5669. A circuit diagram and list
of components for the board is shown in Figs. 10 and 11.
The board can be used for the following purposes:
(A) Measuring RF sensitivity performance.
(B) Indicating port function.
(C) Synthesising a voltage controlled oscillator.
(D) Testing of external reference
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