Motorola PRO Serie Manual De Servicio página 25

DATA_2_VCO
DATA
CLK_2_VCO
CLK
CSX_2_VCO
CSX
C255
R255
UNSWB+_2_VCO
0.5pF 330
UNSWB+
NU
RESET_2_VCO
L253
RESET
390nH
CHASSIS_CONTACTS
M300
L254
0 dBm to RX_FE
C253
RX_LO
82pF
PRESC
C254
Switched supplies for VCOs
68pF
on this page
TX BUFFER
5 mA current draw
5V when selected
R250
270
C286
68pF
R274
120
R254
L252
47K
220nH
C284
Q251
56pF
R271
L250
6.8nH
33
R251
100
C256
L265
1pF
47nH
C290
56pF
4.6 V Super Filter VSF
Supply from U201
R256
0
C259
C262
2.2µF
0.1µF
R275
10 C260
C274
68pF 68pF
33nH
18 14
10 1
TX_OUT TX_IADJ
8 2
RX_OUT RX_IADJ
3
SUPER_FLTR
12 4
PRESC_OUT COLL_RFIN
U250 5
RX_BASE
7 6
Rx_sw
RX_SWITCH RX_EMITTER
13 16
Tx_sw TX_SWITCH TX_BASE
15
TX_EMITTER
20
FLIP_IN
19
TRB_IN
17 11 9
R257
AUX3_5V
1K
C257
68pF
Q252
4
L264
TX_INJ
15nH
R253
10
C283 6 dBm typical
0.5pF
to PA
NU
LEVEL SHIFT FOR VCO SELECT
Allows 3V logic from frac-N to control 5V logic of VCO
RX VCO Components
L259 R264
220nH
270
C267
2pF
R262
C280
33
0.1µF
C266
R273
2pF
33
L260
L258
220nH
220nH
1.9 V when selected
R270
C288
NU
0.5pF
33
C258 R265
30K
0.1µF
VCO Select Line R272
L257
0V for RX
220nH
33
5V for TX
C271
5.6pF
C263
C265
C287
R261
68pF
1.8pF
100pF
33
3
2 L256
AUX4
220nH
1 C268
1pF
R263
270
TX VCO Components
Figura. 4-91 Diagrama eléctrico del oscilador controlado por voltaje de 800MHz (Rev O/A)
Freq Range
741 to 761 MHz
U205
900 MHz
C278
3.9pF
C273
3.3pF
C279
L263
18nH
0.5pF
NU
CR252
C275
1.2pF L262
220nH
R267
C282
68pF
Rx_sw
12K CR253
R269
C269
0
NU
.033µF
DACRX
OPTIONAL BIAS TUNING VOLTAGE
1.9 V when selected
C270
Tx_sw
0.1µF
C285 R266
C289
R268
.033µF 0.1µF 30K
22K
C276
L261
22nH
C272 3pF
CR251 C281
0.5pF
68pF
NU C277
U206
5.6pF
1.225 GHz
Freq Range
SH251
806 to 870 MHz
1
VCO TOP SHIELD
4 -125
VCTRL
Steering Line
2 to 11 VDC
C291
0.5pF
NU
SH250
1
VCO BOTTOM SHIELD