SP5611
j1
j
0.5
j2
j
0.2
j5
0
0.2
0.5
1
2
5
1·25GHz
2
j
5
2
j
0.2
S
11:
Z
O
= 50Ω
NORMALISED TO 50Ω
2
j
0.5
2
j
1
2
j
2
FREQUENCY MARKER STEP
=
250MHz
Fig. 7 Typical input impedance,
APPLICATION NOTES
An application note, AN168, is available for designing with
synthesisers such as the SP5611. It covers aspects such as loop
filter design, decoupling and I
2
C bus radiation problems.
The application note is published in the Mitel Semiconductor
Media IC Handbook. A generic test/demonstration board has
been produced, which can be used for the SP5611. A circuit
diagram and layout for the board are shown in Figs. 8 and 9.
The board can be used for the following purposes:
(A) Measuring RF sensitivity perfomance
(B) Indicating port function
(C) Synthesising a voltage controlled oscillator
(D)Testing external reference sources
The programming codes relevant to these tests are given in
Table 6.
EXTERNAL
REFERENCE
15V
R11 3k
S1
S2
SK2
C7
100n
C3 47n
C2
220n
R7 22k
R12 1k
X1
4MHz
C1
18p
1
2
16
15
14
13
15V
P2
C8
100n
130V
C9
100n
112V
C6 10n
(NOT FITTED,
SEE NOTE)
R8 22k
R9 10k
TR1
2N3904
R10 47k
C14 10n
C5 1n
C4 1n
112V
SK1
RFINPUT
15V
R13 12k
R14 22k
P3
VAR
GND
TP1
DATA/SDA
C12 100p
3
4
5
6
SP5611
12
C10 1n
11
10
9
CLOCK/SCL
C13 100p
7
8
TR2
2N3906
ENABLE/ADDRESS SEL
P1
P4
NOTE
To use an external reference,
capacitor C6 must be fitted
and capacitor C1 removed
from the board.
R1 4·7k
R2 4·7k
R3 4·7k
R4 4·7k
R5 4·7k
R6 4·7k
D1
PIN NO.
6
D2
7
D3
8
D4
9
D5
10
D6
11
112V
C11
1n
Fig. 8 Test board circuit
8
MITEL [ MITEL NETWORKS CORPORATION ]
