EVB72036
868/915MHz FSK/ASK Transmitter
Evaluation Board Description
3 50
Ω
Connector Board Circuit Diagram
Fig. 6:
Circuit diagram with 50
Ω
matching network
3.1
Board Component Values
Size
0805
0805
0805
0805
0805
0805
0805
0805
0805
0805
0805
1206
0805
SMD
6x3.5
0805
Part
CM1
CM2
CM3
LM
LT
CX1
_FSK
CX1
_ASK
CX2
CCK
RPS
R1
CB0
CB1
XTAL
CK
Y
R
A
IN
IM
L
E
R
P
Value @
868.3 MHz
1.8 pF
5.6 pF
68 pF
12 nH
22 pF
27 pF
12pF
Value @
915 MHz
2.2 pF
5.6 pF
68 pF
10 nH
22 pF
27 pF
Toler-
ance
±5%
±5%
±5%
±5%
Description
impedance matching capacitor
impedance matching capacitor
impedance matching inductor
output tank inductor
impedance matching capacitor r
15 nH
10 nH
±5%
±5%
±5%
±5%
±5%
±5%
XOSC FSK capacitor (Δf =
±20
kHz), note 1
XOSC ASK capacitor, trimmed to f
C
, note 1
XOSC capacitor (Δf =
±20
kHz), note 1, only for FSK
capacitor to control clock voltage swing (CKDIV 0 / 1)
power-select resistor, see data sheet section 4.6
ASK jumper (for ASK only), see data sheet sect. 4.7
de-coupling capacitor
de-coupling capacitor
fundamental mode crystal,
C
L
= 12 pF, C
0, max
= 7 pF, R
1
= 40
Ω
12 pF
±5%
15 pF/ 180 pF
NIP
0
Ω
220 nF
330 pF
27.13438 MHz
28.59375 MHz
±30ppm
cali.,
±30ppm
temp
1 nF
±20%
±10%
±10%
ROI coupling capacitor, only required for
external reference frequency input
Note 1:
depends on crystal parameters, other
∆f
values can be selected with other CX1, CX2 values
NIP – not in place, may be used optionally
3901272036 01
Rev. 002
Page 7 of 12
EVB Description
June/07
MELEXIS [ Melexis Microelectronic Systems ]
