sp5669 Mitel, sp5669 Datasheet - Page 9

• Manufacturer Part Number: sp5669
• Description: 2.7ghz I2c Bus Controlled Synthesiser
• Manufacturer: Mitel

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.
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.
Optional application utilising
on–board crystal controlled
oscillator
4MHz
50–900MHz
18pF
Figure. 8 Example of double conversion from VHF/UHF frequencies to TV IF
CONTROL
MICRO
First LO
ADDRESS
REF 10n
SDA
SCL
1650–2700MHz
P3
P2
SP5669
SP5659
Figure. 9 Typical appliction
1.6GHz
15nF
1
1
2
3
4
5
6
7
8
Reference Clock
16
16
15
14
13
12
10
11
9
68pF
13k3
BCW31
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).
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:
+30V
(A) Measuring RF sensitivity performance.
(B) Indicating port function.
(C) Synthesising a voltage controlled oscillator.
(D) Testing of external reference
ADC
P0
P1
22k
1n
1n
Second LO
10n
+5V
16k
OSCILLATOR
OUTPUT
2n2
47k
SP5669
SP5659
38.9MHz
TUNER
+12V
SP5669
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