TH72031 Datasheet, PDF (17/20 Pages) Melexis Microelectronic Systems – 868/915MHz FSK Transmitter

6 Test Circuit
OUT
CM2
CM1
LM CM3
LT
8
7
CB1
RPS
6
5
TH72031
868/915MHz
FSK Transmitter
CX2
XTAL
CX1
12 3
CB0
12 3 12
Fig.18: Test circuit for FSK with 50 Ω matching network
6.1 Test circuit component list to Fig. 18
Part Size Value @
868.3 MHz
Value @
915 MHz
Tolerance
Description
CM1
CM2
CM3
LM
LT
CX1
CX2
RPS
CB0
CB1
XTAL
0805
0805
0805
0805
0805
0805
0805
0805
0805
0805
HC49/S
1.8 pF
2.2 pF
5.6 pF
5.6 pF
68 pF
68 pF
12 nH
10 nH
15 nH
10 nH
18 pF
18 pF
10 pF
10 pF
see section 4.6
220 nF
330 pF
27.13438 MHz 28.59375 MHz
±5%
impedance matching capacitor
±5%
impedance matching capacitor
±5%
impedance matching capacitor
±5%
impedance matching inductor, note 2
±5%
output tank inductor, note 2
±5%
XOSC capacitor (Δf = ±20 kHz), note 1
±5%
XOSC capacitor (Δf = ±20 kHz), note 1
±5%
power-select resistor
±20%
de-coupling capacitor
±10%
de-coupling capacitor
±30ppm calibr. fundamental wave crystal,
±30ppm temp CL = 12 pF, C0, max = 7 pF, R1 = 40 Ω
Note 1: value depending on crystal parameters
Note 2: for high-power applications high-Q wire-wound inductors should be used
3901072031
Rev. 008
Page 17 of 20
Data Sheet
June/07