Motorola MTR2000 T5544 Instruction / Field Service Manual page 173

CLN1226 (40 W) and CLN1227 (30 W) POWER AMPLIFIER MODULE
PA ENABLE
30/40 W INPUT BOARD
MODULATED RF
FROM EXCITER
MODULE
14.2 Vdc
VOLTAGE
TRANSLATOR
SPI BUS
SPI BUS (CLOCK & DATA)
TO/FROM SCM
(VIA BACKPLANE)
D/A AND A/D
CHIP
SELECTS
FROM SCM
+14.2 Vdc
SOURCE
+14.2 Vdc FROM +5 V +5 Vdc
POWER SUPPLY
REGULATOR SOURCE
+28.6 Vdc FROM
+28.6 Vdc
POWER SUPPLY
SOURCE
14.2 Vdc
INTERMEDIATE
BUTTERFLY
POWER AMPLIFIER
MODULE
(IPA)
0 to 10 W
V_OMNI
V_CNTL
PA DA CS*
PA AD CS*
CIRCULATOR * CIRCULATOR *
* TTD1921
ONLY
DIRECTIONAL COUPLER/LOW PASS FILTER
50 OHM 50 OHM
LOAD LOAD
LOW PASS
FILTER
** TTD1781
ONLY
LOW PASS
FILTER **
30/40 W OUTPUT BOARD
I LIMIT SET
D/A
CONVERTER
ID
CHIP
SELECT
T°
PA TEMP
VHF 30/40 W Power Amplifier Modules
DIRECTIONAL
COUPLER
V_OMNI
V_RFLD
V_FWD
FINAL CURRENT
V_CNTL
Σ
PWR SET
PA ID A
PA ID
PA ID B
CIRCUIT
PA TEMP
Figure 2.
68P81096E26-B
09/30/05
TRANSMIT RF OUTPUT
TO TRANSMIT
SPI BUS (CLOCK & DATA)
A/D
CONVERTER
CHIP
SELECT
VHF 30/40 W Power Amplifiers
Functional Block Diagram
5